--- /dev/null
+/*
+ * transupp.c
+ *
+ * Copyright (C) 1997-2001, Thomas G. Lane.
+ * This file is part of the Independent JPEG Group's software.
+ * For conditions of distribution and use, see the accompanying README file.
+ *
+ * This file contains image transformation routines and other utility code
+ * used by the jpegtran sample application. These are NOT part of the core
+ * JPEG library. But we keep these routines separate from jpegtran.c to
+ * ease the task of maintaining jpegtran-like programs that have other user
+ * interfaces.
+ */
+
+/* Although this file really shouldn't have access to the library internals,
+ * it's helpful to let it call jround_up() and jcopy_block_row().
+ */
+#define JPEG_INTERNALS
+
+#include "jinclude.h"
+#include "jpeglib.h"
+#include "transupp.h" /* My own external interface */
+#include <ctype.h> /* to declare isdigit() */
+
+
+#if TRANSFORMS_SUPPORTED
+
+/*
+ * Lossless image transformation routines. These routines work on DCT
+ * coefficient arrays and thus do not require any lossy decompression
+ * or recompression of the image.
+ * Thanks to Guido Vollbeding for the initial design and code of this feature,
+ * and to Ben Jackson for introducing the cropping feature.
+ *
+ * Horizontal flipping is done in-place, using a single top-to-bottom
+ * pass through the virtual source array. It will thus be much the
+ * fastest option for images larger than main memory.
+ *
+ * The other routines require a set of destination virtual arrays, so they
+ * need twice as much memory as jpegtran normally does. The destination
+ * arrays are always written in normal scan order (top to bottom) because
+ * the virtual array manager expects this. The source arrays will be scanned
+ * in the corresponding order, which means multiple passes through the source
+ * arrays for most of the transforms. That could result in much thrashing
+ * if the image is larger than main memory.
+ *
+ * If cropping or trimming is involved, the destination arrays may be smaller
+ * than the source arrays. Note it is not possible to do horizontal flip
+ * in-place when a nonzero Y crop offset is specified, since we'd have to move
+ * data from one block row to another but the virtual array manager doesn't
+ * guarantee we can touch more than one row at a time. So in that case,
+ * we have to use a separate destination array.
+ *
+ * Some notes about the operating environment of the individual transform
+ * routines:
+ * 1. Both the source and destination virtual arrays are allocated from the
+ * source JPEG object, and therefore should be manipulated by calling the
+ * source's memory manager.
+ * 2. The destination's component count should be used. It may be smaller
+ * than the source's when forcing to grayscale.
+ * 3. Likewise the destination's sampling factors should be used. When
+ * forcing to grayscale the destination's sampling factors will be all 1,
+ * and we may as well take that as the effective iMCU size.
+ * 4. When "trim" is in effect, the destination's dimensions will be the
+ * trimmed values but the source's will be untrimmed.
+ * 5. When "crop" is in effect, the destination's dimensions will be the
+ * cropped values but the source's will be uncropped. Each transform
+ * routine is responsible for picking up source data starting at the
+ * correct X and Y offset for the crop region. (The X and Y offsets
+ * passed to the transform routines are measured in iMCU blocks of the
+ * destination.)
+ * 6. All the routines assume that the source and destination buffers are
+ * padded out to a full iMCU boundary. This is true, although for the
+ * source buffer it is an undocumented property of jdcoefct.c.
+ */
+
+
+LOCAL(void)
+do_crop (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
+ JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
+ jvirt_barray_ptr *src_coef_arrays,
+ jvirt_barray_ptr *dst_coef_arrays)
+/* Crop. This is only used when no rotate/flip is requested with the crop. */
+{
+ JDIMENSION dst_blk_y, x_crop_blocks, y_crop_blocks;
+ int ci, offset_y;
+ JBLOCKARRAY src_buffer, dst_buffer;
+ jpeg_component_info *compptr;
+
+ /* We simply have to copy the right amount of data (the destination's
+ * image size) starting at the given X and Y offsets in the source.
+ */
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
+ y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
+ for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
+ dst_blk_y += compptr->v_samp_factor) {
+ dst_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
+ (JDIMENSION) compptr->v_samp_factor, TRUE);
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
+ dst_blk_y + y_crop_blocks,
+ (JDIMENSION) compptr->v_samp_factor, FALSE);
+ for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
+ jcopy_block_row(src_buffer[offset_y] + x_crop_blocks,
+ dst_buffer[offset_y],
+ compptr->width_in_blocks);
+ }
+ }
+ }
+}
+
+
+LOCAL(void)
+do_flip_h_no_crop (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
+ JDIMENSION x_crop_offset,
+ jvirt_barray_ptr *src_coef_arrays)
+/* Horizontal flip; done in-place, so no separate dest array is required.
+ * NB: this only works when y_crop_offset is zero.
+ */
+{
+ JDIMENSION MCU_cols, comp_width, blk_x, blk_y, x_crop_blocks;
+ int ci, k, offset_y;
+ JBLOCKARRAY buffer;
+ JCOEFPTR ptr1, ptr2;
+ JCOEF temp1, temp2;
+ jpeg_component_info *compptr;
+
+ /* Horizontal mirroring of DCT blocks is accomplished by swapping
+ * pairs of blocks in-place. Within a DCT block, we perform horizontal
+ * mirroring by changing the signs of odd-numbered columns.
+ * Partial iMCUs at the right edge are left untouched.
+ */
+ MCU_cols = srcinfo->image_width / (dstinfo->max_h_samp_factor * DCTSIZE);
+
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+ comp_width = MCU_cols * compptr->h_samp_factor;
+ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
+ for (blk_y = 0; blk_y < compptr->height_in_blocks;
+ blk_y += compptr->v_samp_factor) {
+ buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, src_coef_arrays[ci], blk_y,
+ (JDIMENSION) compptr->v_samp_factor, TRUE);
+ for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
+ /* Do the mirroring */
+ for (blk_x = 0; blk_x * 2 < comp_width; blk_x++) {
+ ptr1 = buffer[offset_y][blk_x];
+ ptr2 = buffer[offset_y][comp_width - blk_x - 1];
+ /* this unrolled loop doesn't need to know which row it's on... */
+ for (k = 0; k < DCTSIZE2; k += 2) {
+ temp1 = *ptr1; /* swap even column */
+ temp2 = *ptr2;
+ *ptr1++ = temp2;
+ *ptr2++ = temp1;
+ temp1 = *ptr1; /* swap odd column with sign change */
+ temp2 = *ptr2;
+ *ptr1++ = -temp2;
+ *ptr2++ = -temp1;
+ }
+ }
+ if (x_crop_blocks > 0) {
+ /* Now left-justify the portion of the data to be kept.
+ * We can't use a single jcopy_block_row() call because that routine
+ * depends on memcpy(), whose behavior is unspecified for overlapping
+ * source and destination areas. Sigh.
+ */
+ for (blk_x = 0; blk_x < compptr->width_in_blocks; blk_x++) {
+ jcopy_block_row(buffer[offset_y] + blk_x + x_crop_blocks,
+ buffer[offset_y] + blk_x,
+ (JDIMENSION) 1);
+ }
+ }
+ }
+ }
+ }
+}
+
+
+LOCAL(void)
+do_flip_h (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
+ JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
+ jvirt_barray_ptr *src_coef_arrays,
+ jvirt_barray_ptr *dst_coef_arrays)
+/* Horizontal flip in general cropping case */
+{
+ JDIMENSION MCU_cols, comp_width, dst_blk_x, dst_blk_y;
+ JDIMENSION x_crop_blocks, y_crop_blocks;
+ int ci, k, offset_y;
+ JBLOCKARRAY src_buffer, dst_buffer;
+ JBLOCKROW src_row_ptr, dst_row_ptr;
+ JCOEFPTR src_ptr, dst_ptr;
+ jpeg_component_info *compptr;
+
+ /* Here we must output into a separate array because we can't touch
+ * different rows of a single virtual array simultaneously. Otherwise,
+ * this is essentially the same as the routine above.
+ */
+ MCU_cols = srcinfo->image_width / (dstinfo->max_h_samp_factor * DCTSIZE);
+
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+ comp_width = MCU_cols * compptr->h_samp_factor;
+ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
+ y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
+ for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
+ dst_blk_y += compptr->v_samp_factor) {
+ dst_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
+ (JDIMENSION) compptr->v_samp_factor, TRUE);
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
+ dst_blk_y + y_crop_blocks,
+ (JDIMENSION) compptr->v_samp_factor, FALSE);
+ for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
+ dst_row_ptr = dst_buffer[offset_y];
+ src_row_ptr = src_buffer[offset_y];
+ for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {
+ if (x_crop_blocks + dst_blk_x < comp_width) {
+ /* Do the mirrorable blocks */
+ dst_ptr = dst_row_ptr[dst_blk_x];
+ src_ptr = src_row_ptr[comp_width - x_crop_blocks - dst_blk_x - 1];
+ /* this unrolled loop doesn't need to know which row it's on... */
+ for (k = 0; k < DCTSIZE2; k += 2) {
+ *dst_ptr++ = *src_ptr++; /* copy even column */
+ *dst_ptr++ = - *src_ptr++; /* copy odd column with sign change */
+ }
+ } else {
+ /* Copy last partial block(s) verbatim */
+ jcopy_block_row(src_row_ptr + dst_blk_x + x_crop_blocks,
+ dst_row_ptr + dst_blk_x,
+ (JDIMENSION) 1);
+ }
+ }
+ }
+ }
+ }
+}
+
+
+LOCAL(void)
+do_flip_v (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
+ JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
+ jvirt_barray_ptr *src_coef_arrays,
+ jvirt_barray_ptr *dst_coef_arrays)
+/* Vertical flip */
+{
+ JDIMENSION MCU_rows, comp_height, dst_blk_x, dst_blk_y;
+ JDIMENSION x_crop_blocks, y_crop_blocks;
+ int ci, i, j, offset_y;
+ JBLOCKARRAY src_buffer, dst_buffer;
+ JBLOCKROW src_row_ptr, dst_row_ptr;
+ JCOEFPTR src_ptr, dst_ptr;
+ jpeg_component_info *compptr;
+
+ /* We output into a separate array because we can't touch different
+ * rows of the source virtual array simultaneously. Otherwise, this
+ * is a pretty straightforward analog of horizontal flip.
+ * Within a DCT block, vertical mirroring is done by changing the signs
+ * of odd-numbered rows.
+ * Partial iMCUs at the bottom edge are copied verbatim.
+ */
+ MCU_rows = srcinfo->image_height / (dstinfo->max_v_samp_factor * DCTSIZE);
+
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+ comp_height = MCU_rows * compptr->v_samp_factor;
+ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
+ y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
+ for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
+ dst_blk_y += compptr->v_samp_factor) {
+ dst_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
+ (JDIMENSION) compptr->v_samp_factor, TRUE);
+ if (y_crop_blocks + dst_blk_y < comp_height) {
+ /* Row is within the mirrorable area. */
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
+ comp_height - y_crop_blocks - dst_blk_y -
+ (JDIMENSION) compptr->v_samp_factor,
+ (JDIMENSION) compptr->v_samp_factor, FALSE);
+ } else {
+ /* Bottom-edge blocks will be copied verbatim. */
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
+ dst_blk_y + y_crop_blocks,
+ (JDIMENSION) compptr->v_samp_factor, FALSE);
+ }
+ for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
+ if (y_crop_blocks + dst_blk_y < comp_height) {
+ /* Row is within the mirrorable area. */
+ dst_row_ptr = dst_buffer[offset_y];
+ src_row_ptr = src_buffer[compptr->v_samp_factor - offset_y - 1];
+ src_row_ptr += x_crop_blocks;
+ for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
+ dst_blk_x++) {
+ dst_ptr = dst_row_ptr[dst_blk_x];
+ src_ptr = src_row_ptr[dst_blk_x];
+ for (i = 0; i < DCTSIZE; i += 2) {
+ /* copy even row */
+ for (j = 0; j < DCTSIZE; j++)
+ *dst_ptr++ = *src_ptr++;
+ /* copy odd row with sign change */
+ for (j = 0; j < DCTSIZE; j++)
+ *dst_ptr++ = - *src_ptr++;
+ }
+ }
+ } else {
+ /* Just copy row verbatim. */
+ jcopy_block_row(src_buffer[offset_y] + x_crop_blocks,
+ dst_buffer[offset_y],
+ compptr->width_in_blocks);
+ }
+ }
+ }
+ }
+}
+
+
+LOCAL(void)
+do_transpose (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
+ JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
+ jvirt_barray_ptr *src_coef_arrays,
+ jvirt_barray_ptr *dst_coef_arrays)
+/* Transpose source into destination */
+{
+ JDIMENSION dst_blk_x, dst_blk_y, x_crop_blocks, y_crop_blocks;
+ int ci, i, j, offset_x, offset_y;
+ JBLOCKARRAY src_buffer, dst_buffer;
+ JCOEFPTR src_ptr, dst_ptr;
+ jpeg_component_info *compptr;
+
+ /* Transposing pixels within a block just requires transposing the
+ * DCT coefficients.
+ * Partial iMCUs at the edges require no special treatment; we simply
+ * process all the available DCT blocks for every component.
+ */
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
+ y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
+ for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
+ dst_blk_y += compptr->v_samp_factor) {
+ dst_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
+ (JDIMENSION) compptr->v_samp_factor, TRUE);
+ for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
+ for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
+ dst_blk_x += compptr->h_samp_factor) {
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
+ dst_blk_x + x_crop_blocks,
+ (JDIMENSION) compptr->h_samp_factor, FALSE);
+ for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {
+ dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
+ src_ptr = src_buffer[offset_x][dst_blk_y + offset_y + y_crop_blocks];
+ for (i = 0; i < DCTSIZE; i++)
+ for (j = 0; j < DCTSIZE; j++)
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+ }
+ }
+ }
+ }
+ }
+}
+
+
+LOCAL(void)
+do_rot_90 (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
+ JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
+ jvirt_barray_ptr *src_coef_arrays,
+ jvirt_barray_ptr *dst_coef_arrays)
+/* 90 degree rotation is equivalent to
+ * 1. Transposing the image;
+ * 2. Horizontal mirroring.
+ * These two steps are merged into a single processing routine.
+ */
+{
+ JDIMENSION MCU_cols, comp_width, dst_blk_x, dst_blk_y;
+ JDIMENSION x_crop_blocks, y_crop_blocks;
+ int ci, i, j, offset_x, offset_y;
+ JBLOCKARRAY src_buffer, dst_buffer;
+ JCOEFPTR src_ptr, dst_ptr;
+ jpeg_component_info *compptr;
+
+ /* Because of the horizontal mirror step, we can't process partial iMCUs
+ * at the (output) right edge properly. They just get transposed and
+ * not mirrored.
+ */
+ MCU_cols = srcinfo->image_height / (dstinfo->max_h_samp_factor * DCTSIZE);
+
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+ comp_width = MCU_cols * compptr->h_samp_factor;
+ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
+ y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
+ for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
+ dst_blk_y += compptr->v_samp_factor) {
+ dst_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
+ (JDIMENSION) compptr->v_samp_factor, TRUE);
+ for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
+ for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
+ dst_blk_x += compptr->h_samp_factor) {
+ if (x_crop_blocks + dst_blk_x < comp_width) {
+ /* Block is within the mirrorable area. */
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
+ comp_width - x_crop_blocks - dst_blk_x -
+ (JDIMENSION) compptr->h_samp_factor,
+ (JDIMENSION) compptr->h_samp_factor, FALSE);
+ } else {
+ /* Edge blocks are transposed but not mirrored. */
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
+ dst_blk_x + x_crop_blocks,
+ (JDIMENSION) compptr->h_samp_factor, FALSE);
+ }
+ for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {
+ dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
+ if (x_crop_blocks + dst_blk_x < comp_width) {
+ /* Block is within the mirrorable area. */
+ src_ptr = src_buffer[compptr->h_samp_factor - offset_x - 1]
+ [dst_blk_y + offset_y + y_crop_blocks];
+ for (i = 0; i < DCTSIZE; i++) {
+ for (j = 0; j < DCTSIZE; j++)
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+ i++;
+ for (j = 0; j < DCTSIZE; j++)
+ dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];
+ }
+ } else {
+ /* Edge blocks are transposed but not mirrored. */
+ src_ptr = src_buffer[offset_x]
+ [dst_blk_y + offset_y + y_crop_blocks];
+ for (i = 0; i < DCTSIZE; i++)
+ for (j = 0; j < DCTSIZE; j++)
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+ }
+ }
+ }
+ }
+ }
+ }
+}
+
+
+LOCAL(void)
+do_rot_270 (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
+ JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
+ jvirt_barray_ptr *src_coef_arrays,
+ jvirt_barray_ptr *dst_coef_arrays)
+/* 270 degree rotation is equivalent to
+ * 1. Horizontal mirroring;
+ * 2. Transposing the image.
+ * These two steps are merged into a single processing routine.
+ */
+{
+ JDIMENSION MCU_rows, comp_height, dst_blk_x, dst_blk_y;
+ JDIMENSION x_crop_blocks, y_crop_blocks;
+ int ci, i, j, offset_x, offset_y;
+ JBLOCKARRAY src_buffer, dst_buffer;
+ JCOEFPTR src_ptr, dst_ptr;
+ jpeg_component_info *compptr;
+
+ /* Because of the horizontal mirror step, we can't process partial iMCUs
+ * at the (output) bottom edge properly. They just get transposed and
+ * not mirrored.
+ */
+ MCU_rows = srcinfo->image_width / (dstinfo->max_v_samp_factor * DCTSIZE);
+
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+ comp_height = MCU_rows * compptr->v_samp_factor;
+ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
+ y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
+ for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
+ dst_blk_y += compptr->v_samp_factor) {
+ dst_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
+ (JDIMENSION) compptr->v_samp_factor, TRUE);
+ for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
+ for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
+ dst_blk_x += compptr->h_samp_factor) {
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
+ dst_blk_x + x_crop_blocks,
+ (JDIMENSION) compptr->h_samp_factor, FALSE);
+ for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {
+ dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
+ if (y_crop_blocks + dst_blk_y < comp_height) {
+ /* Block is within the mirrorable area. */
+ src_ptr = src_buffer[offset_x]
+ [comp_height - y_crop_blocks - dst_blk_y - offset_y - 1];
+ for (i = 0; i < DCTSIZE; i++) {
+ for (j = 0; j < DCTSIZE; j++) {
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+ j++;
+ dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];
+ }
+ }
+ } else {
+ /* Edge blocks are transposed but not mirrored. */
+ src_ptr = src_buffer[offset_x]
+ [dst_blk_y + offset_y + y_crop_blocks];
+ for (i = 0; i < DCTSIZE; i++)
+ for (j = 0; j < DCTSIZE; j++)
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+ }
+ }
+ }
+ }
+ }
+ }
+}
+
+
+LOCAL(void)
+do_rot_180 (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
+ JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
+ jvirt_barray_ptr *src_coef_arrays,
+ jvirt_barray_ptr *dst_coef_arrays)
+/* 180 degree rotation is equivalent to
+ * 1. Vertical mirroring;
+ * 2. Horizontal mirroring.
+ * These two steps are merged into a single processing routine.
+ */
+{
+ JDIMENSION MCU_cols, MCU_rows, comp_width, comp_height, dst_blk_x, dst_blk_y;
+ JDIMENSION x_crop_blocks, y_crop_blocks;
+ int ci, i, j, offset_y;
+ JBLOCKARRAY src_buffer, dst_buffer;
+ JBLOCKROW src_row_ptr, dst_row_ptr;
+ JCOEFPTR src_ptr, dst_ptr;
+ jpeg_component_info *compptr;
+
+ MCU_cols = srcinfo->image_width / (dstinfo->max_h_samp_factor * DCTSIZE);
+ MCU_rows = srcinfo->image_height / (dstinfo->max_v_samp_factor * DCTSIZE);
+
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+ comp_width = MCU_cols * compptr->h_samp_factor;
+ comp_height = MCU_rows * compptr->v_samp_factor;
+ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
+ y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
+ for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
+ dst_blk_y += compptr->v_samp_factor) {
+ dst_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
+ (JDIMENSION) compptr->v_samp_factor, TRUE);
+ if (y_crop_blocks + dst_blk_y < comp_height) {
+ /* Row is within the vertically mirrorable area. */
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
+ comp_height - y_crop_blocks - dst_blk_y -
+ (JDIMENSION) compptr->v_samp_factor,
+ (JDIMENSION) compptr->v_samp_factor, FALSE);
+ } else {
+ /* Bottom-edge rows are only mirrored horizontally. */
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
+ dst_blk_y + y_crop_blocks,
+ (JDIMENSION) compptr->v_samp_factor, FALSE);
+ }
+ for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
+ dst_row_ptr = dst_buffer[offset_y];
+ if (y_crop_blocks + dst_blk_y < comp_height) {
+ /* Row is within the mirrorable area. */
+ src_row_ptr = src_buffer[compptr->v_samp_factor - offset_y - 1];
+ for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {
+ dst_ptr = dst_row_ptr[dst_blk_x];
+ if (x_crop_blocks + dst_blk_x < comp_width) {
+ /* Process the blocks that can be mirrored both ways. */
+ src_ptr = src_row_ptr[comp_width - x_crop_blocks - dst_blk_x - 1];
+ for (i = 0; i < DCTSIZE; i += 2) {
+ /* For even row, negate every odd column. */
+ for (j = 0; j < DCTSIZE; j += 2) {
+ *dst_ptr++ = *src_ptr++;
+ *dst_ptr++ = - *src_ptr++;
+ }
+ /* For odd row, negate every even column. */
+ for (j = 0; j < DCTSIZE; j += 2) {
+ *dst_ptr++ = - *src_ptr++;
+ *dst_ptr++ = *src_ptr++;
+ }
+ }
+ } else {
+ /* Any remaining right-edge blocks are only mirrored vertically. */
+ src_ptr = src_row_ptr[x_crop_blocks + dst_blk_x];
+ for (i = 0; i < DCTSIZE; i += 2) {
+ for (j = 0; j < DCTSIZE; j++)
+ *dst_ptr++ = *src_ptr++;
+ for (j = 0; j < DCTSIZE; j++)
+ *dst_ptr++ = - *src_ptr++;
+ }
+ }
+ }
+ } else {
+ /* Remaining rows are just mirrored horizontally. */
+ src_row_ptr = src_buffer[offset_y];
+ for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {
+ if (x_crop_blocks + dst_blk_x < comp_width) {
+ /* Process the blocks that can be mirrored. */
+ dst_ptr = dst_row_ptr[dst_blk_x];
+ src_ptr = src_row_ptr[comp_width - x_crop_blocks - dst_blk_x - 1];
+ for (i = 0; i < DCTSIZE2; i += 2) {
+ *dst_ptr++ = *src_ptr++;
+ *dst_ptr++ = - *src_ptr++;
+ }
+ } else {
+ /* Any remaining right-edge blocks are only copied. */
+ jcopy_block_row(src_row_ptr + dst_blk_x + x_crop_blocks,
+ dst_row_ptr + dst_blk_x,
+ (JDIMENSION) 1);
+ }
+ }
+ }
+ }
+ }
+ }
+}
+
+
+LOCAL(void)
+do_transverse (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
+ JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
+ jvirt_barray_ptr *src_coef_arrays,
+ jvirt_barray_ptr *dst_coef_arrays)
+/* Transverse transpose is equivalent to
+ * 1. 180 degree rotation;
+ * 2. Transposition;
+ * or
+ * 1. Horizontal mirroring;
+ * 2. Transposition;
+ * 3. Horizontal mirroring.
+ * These steps are merged into a single processing routine.
+ */
+{
+ JDIMENSION MCU_cols, MCU_rows, comp_width, comp_height, dst_blk_x, dst_blk_y;
+ JDIMENSION x_crop_blocks, y_crop_blocks;
+ int ci, i, j, offset_x, offset_y;
+ JBLOCKARRAY src_buffer, dst_buffer;
+ JCOEFPTR src_ptr, dst_ptr;
+ jpeg_component_info *compptr;
+
+ MCU_cols = srcinfo->image_height / (dstinfo->max_h_samp_factor * DCTSIZE);
+ MCU_rows = srcinfo->image_width / (dstinfo->max_v_samp_factor * DCTSIZE);
+
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+ comp_width = MCU_cols * compptr->h_samp_factor;
+ comp_height = MCU_rows * compptr->v_samp_factor;
+ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
+ y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
+ for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
+ dst_blk_y += compptr->v_samp_factor) {
+ dst_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
+ (JDIMENSION) compptr->v_samp_factor, TRUE);
+ for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
+ for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
+ dst_blk_x += compptr->h_samp_factor) {
+ if (x_crop_blocks + dst_blk_x < comp_width) {
+ /* Block is within the mirrorable area. */
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
+ comp_width - x_crop_blocks - dst_blk_x -
+ (JDIMENSION) compptr->h_samp_factor,
+ (JDIMENSION) compptr->h_samp_factor, FALSE);
+ } else {
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
+ dst_blk_x + x_crop_blocks,
+ (JDIMENSION) compptr->h_samp_factor, FALSE);
+ }
+ for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {
+ dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
+ if (y_crop_blocks + dst_blk_y < comp_height) {
+ if (x_crop_blocks + dst_blk_x < comp_width) {
+ /* Block is within the mirrorable area. */
+ src_ptr = src_buffer[compptr->h_samp_factor - offset_x - 1]
+ [comp_height - y_crop_blocks - dst_blk_y - offset_y - 1];
+ for (i = 0; i < DCTSIZE; i++) {
+ for (j = 0; j < DCTSIZE; j++) {
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+ j++;
+ dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];
+ }
+ i++;
+ for (j = 0; j < DCTSIZE; j++) {
+ dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];
+ j++;
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+ }
+ }
+ } else {
+ /* Right-edge blocks are mirrored in y only */
+ src_ptr = src_buffer[offset_x]
+ [comp_height - y_crop_blocks - dst_blk_y - offset_y - 1];
+ for (i = 0; i < DCTSIZE; i++) {
+ for (j = 0; j < DCTSIZE; j++) {
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+ j++;
+ dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];
+ }
+ }
+ }
+ } else {
+ if (x_crop_blocks + dst_blk_x < comp_width) {
+ /* Bottom-edge blocks are mirrored in x only */
+ src_ptr = src_buffer[compptr->h_samp_factor - offset_x - 1]
+ [dst_blk_y + offset_y + y_crop_blocks];
+ for (i = 0; i < DCTSIZE; i++) {
+ for (j = 0; j < DCTSIZE; j++)
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+ i++;
+ for (j = 0; j < DCTSIZE; j++)
+ dst_ptr[j*DCTSIZE+i] = -src_ptr[i*DCTSIZE+j];
+ }
+ } else {
+ /* At lower right corner, just transpose, no mirroring */
+ src_ptr = src_buffer[offset_x]
+ [dst_blk_y + offset_y + y_crop_blocks];
+ for (i = 0; i < DCTSIZE; i++)
+ for (j = 0; j < DCTSIZE; j++)
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+}
+
+
+/* Parse an unsigned integer: subroutine for jtransform_parse_crop_spec.
+ * Returns TRUE if valid integer found, FALSE if not.
+ * *strptr is advanced over the digit string, and *result is set to its value.
+ */
+
+LOCAL(boolean)
+jt_read_integer (const char ** strptr, JDIMENSION * result)
+{
+ const char * ptr = *strptr;
+ JDIMENSION val = 0;
+
+ for (; isdigit(*ptr); ptr++) {
+ val = val * 10 + (JDIMENSION) (*ptr - '0');
+ }
+ *result = val;
+ if (ptr == *strptr)
+ return FALSE; /* oops, no digits */
+ *strptr = ptr;
+ return TRUE;
+}
+
+
+/* Parse a crop specification (written in X11 geometry style).
+ * The routine returns TRUE if the spec string is valid, FALSE if not.
+ *
+ * The crop spec string should have the format
+ * <width>x<height>{+-}<xoffset>{+-}<yoffset>
+ * where width, height, xoffset, and yoffset are unsigned integers.
+ * Each of the elements can be omitted to indicate a default value.
+ * (A weakness of this style is that it is not possible to omit xoffset
+ * while specifying yoffset, since they look alike.)
+ *
+ * This code is loosely based on XParseGeometry from the X11 distribution.
+ */
+
+GLOBAL(boolean)
+jtransform_parse_crop_spec (jpeg_transform_info *info, const char *spec)
+{
+ info->crop = FALSE;
+ info->crop_width_set = JCROP_UNSET;
+ info->crop_height_set = JCROP_UNSET;
+ info->crop_xoffset_set = JCROP_UNSET;
+ info->crop_yoffset_set = JCROP_UNSET;
+
+ if (isdigit(*spec)) {
+ /* fetch width */
+ if (! jt_read_integer(&spec, &info->crop_width))
+ return FALSE;
+ info->crop_width_set = JCROP_POS;
+ }
+ if (*spec == 'x' || *spec == 'X') {
+ /* fetch height */
+ spec++;
+ if (! jt_read_integer(&spec, &info->crop_height))
+ return FALSE;
+ info->crop_height_set = JCROP_POS;
+ }
+ if (*spec == '+' || *spec == '-') {
+ /* fetch xoffset */
+ info->crop_xoffset_set = (*spec == '-') ? JCROP_NEG : JCROP_POS;
+ spec++;
+ if (! jt_read_integer(&spec, &info->crop_xoffset))
+ return FALSE;
+ }
+ if (*spec == '+' || *spec == '-') {
+ /* fetch yoffset */
+ info->crop_yoffset_set = (*spec == '-') ? JCROP_NEG : JCROP_POS;
+ spec++;
+ if (! jt_read_integer(&spec, &info->crop_yoffset))
+ return FALSE;
+ }
+ /* We had better have gotten to the end of the string. */
+ if (*spec != '\0')
+ return FALSE;
+ info->crop = TRUE;
+ return TRUE;
+}
+
+
+/* Trim off any partial iMCUs on the indicated destination edge */
+
+LOCAL(void)
+trim_right_edge (jpeg_transform_info *info, JDIMENSION full_width)
+{
+ JDIMENSION MCU_cols;
+
+ MCU_cols = info->output_width / (info->max_h_samp_factor * DCTSIZE);
+ if (MCU_cols > 0 && info->x_crop_offset + MCU_cols ==
+ full_width / (info->max_h_samp_factor * DCTSIZE))
+ info->output_width = MCU_cols * (info->max_h_samp_factor * DCTSIZE);
+}
+
+LOCAL(void)
+trim_bottom_edge (jpeg_transform_info *info, JDIMENSION full_height)
+{
+ JDIMENSION MCU_rows;
+
+ MCU_rows = info->output_height / (info->max_v_samp_factor * DCTSIZE);
+ if (MCU_rows > 0 && info->y_crop_offset + MCU_rows ==
+ full_height / (info->max_v_samp_factor * DCTSIZE))
+ info->output_height = MCU_rows * (info->max_v_samp_factor * DCTSIZE);
+}
+
+
+/* Request any required workspace.
+ *
+ * This routine figures out the size that the output image will be
+ * (which implies that all the transform parameters must be set before
+ * it is called).
+ *
+ * We allocate the workspace virtual arrays from the source decompression
+ * object, so that all the arrays (both the original data and the workspace)
+ * will be taken into account while making memory management decisions.
+ * Hence, this routine must be called after jpeg_read_header (which reads
+ * the image dimensions) and before jpeg_read_coefficients (which realizes
+ * the source's virtual arrays).
+ */
+
+GLOBAL(void)
+jtransform_request_workspace (j_decompress_ptr srcinfo,
+ jpeg_transform_info *info)
+{
+ jvirt_barray_ptr *coef_arrays = NULL;
+ boolean need_workspace, transpose_it;
+ jpeg_component_info *compptr;
+ JDIMENSION xoffset, yoffset, width_in_iMCUs, height_in_iMCUs;
+ JDIMENSION width_in_blocks, height_in_blocks;
+ int ci, h_samp_factor, v_samp_factor;
+
+ /* Determine number of components in output image */
+ if (info->force_grayscale &&
+ srcinfo->jpeg_color_space == JCS_YCbCr &&
+ srcinfo->num_components == 3) {
+ /* We'll only process the first component */
+ info->num_components = 1;
+ } else {
+ /* Process all the components */
+ info->num_components = srcinfo->num_components;
+ }
+ /* If there is only one output component, force the iMCU size to be 1;
+ * else use the source iMCU size. (This allows us to do the right thing
+ * when reducing color to grayscale, and also provides a handy way of
+ * cleaning up "funny" grayscale images whose sampling factors are not 1x1.)
+ */
+
+ switch (info->transform) {
+ case JXFORM_TRANSPOSE:
+ case JXFORM_TRANSVERSE:
+ case JXFORM_ROT_90:
+ case JXFORM_ROT_270:
+ info->output_width = srcinfo->image_height;
+ info->output_height = srcinfo->image_width;
+ if (info->num_components == 1) {
+ info->max_h_samp_factor = 1;
+ info->max_v_samp_factor = 1;
+ } else {
+ info->max_h_samp_factor = srcinfo->max_v_samp_factor;
+ info->max_v_samp_factor = srcinfo->max_h_samp_factor;
+ }
+ break;
+ default:
+ info->output_width = srcinfo->image_width;
+ info->output_height = srcinfo->image_height;
+ if (info->num_components == 1) {
+ info->max_h_samp_factor = 1;
+ info->max_v_samp_factor = 1;
+ } else {
+ info->max_h_samp_factor = srcinfo->max_h_samp_factor;
+ info->max_v_samp_factor = srcinfo->max_v_samp_factor;
+ }
+ break;
+ }
+
+ /* If cropping has been requested, compute the crop area's position and
+ * dimensions, ensuring that its upper left corner falls at an iMCU boundary.
+ */
+ if (info->crop) {
+ /* Insert default values for unset crop parameters */
+ if (info->crop_xoffset_set == JCROP_UNSET)
+ info->crop_xoffset = 0; /* default to +0 */
+ if (info->crop_yoffset_set == JCROP_UNSET)
+ info->crop_yoffset = 0; /* default to +0 */
+ if (info->crop_xoffset >= info->output_width ||
+ info->crop_yoffset >= info->output_height)
+ ERREXIT(srcinfo, JERR_BAD_CROP_SPEC);
+ if (info->crop_width_set == JCROP_UNSET)
+ info->crop_width = info->output_width - info->crop_xoffset;
+ if (info->crop_height_set == JCROP_UNSET)
+ info->crop_height = info->output_height - info->crop_yoffset;
+ /* Ensure parameters are valid */
+ if (info->crop_width <= 0 || info->crop_width > info->output_width ||
+ info->crop_height <= 0 || info->crop_height > info->output_height ||
+ info->crop_xoffset > info->output_width - info->crop_width ||
+ info->crop_yoffset > info->output_height - info->crop_height)
+ ERREXIT(srcinfo, JERR_BAD_CROP_SPEC);
+ /* Convert negative crop offsets into regular offsets */
+ if (info->crop_xoffset_set == JCROP_NEG)
+ xoffset = info->output_width - info->crop_width - info->crop_xoffset;
+ else
+ xoffset = info->crop_xoffset;
+ if (info->crop_yoffset_set == JCROP_NEG)
+ yoffset = info->output_height - info->crop_height - info->crop_yoffset;
+ else
+ yoffset = info->crop_yoffset;
+ /* Now adjust so that upper left corner falls at an iMCU boundary */
+ info->output_width =
+ info->crop_width + (xoffset % (info->max_h_samp_factor * DCTSIZE));
+ info->output_height =
+ info->crop_height + (yoffset % (info->max_v_samp_factor * DCTSIZE));
+ /* Save x/y offsets measured in iMCUs */
+ info->x_crop_offset = xoffset / (info->max_h_samp_factor * DCTSIZE);
+ info->y_crop_offset = yoffset / (info->max_v_samp_factor * DCTSIZE);
+ } else {
+ info->x_crop_offset = 0;
+ info->y_crop_offset = 0;
+ }
+
+ /* Figure out whether we need workspace arrays,
+ * and if so whether they are transposed relative to the source.
+ */
+ need_workspace = FALSE;
+ transpose_it = FALSE;
+ switch (info->transform) {
+ case JXFORM_NONE:
+ if (info->x_crop_offset != 0 || info->y_crop_offset != 0)
+ need_workspace = TRUE;
+ /* No workspace needed if neither cropping nor transforming */
+ break;
+ case JXFORM_FLIP_H:
+ if (info->trim)
+ trim_right_edge(info, srcinfo->image_width);
+ if (info->y_crop_offset != 0)
+ need_workspace = TRUE;
+ /* do_flip_h_no_crop doesn't need a workspace array */
+ break;
+ case JXFORM_FLIP_V:
+ if (info->trim)
+ trim_bottom_edge(info, srcinfo->image_height);
+ /* Need workspace arrays having same dimensions as source image. */
+ need_workspace = TRUE;
+ break;
+ case JXFORM_TRANSPOSE:
+ /* transpose does NOT have to trim anything */
+ /* Need workspace arrays having transposed dimensions. */
+ need_workspace = TRUE;
+ transpose_it = TRUE;
+ break;
+ case JXFORM_TRANSVERSE:
+ if (info->trim) {
+ trim_right_edge(info, srcinfo->image_height);
+ trim_bottom_edge(info, srcinfo->image_width);
+ }
+ /* Need workspace arrays having transposed dimensions. */
+ need_workspace = TRUE;
+ transpose_it = TRUE;
+ break;
+ case JXFORM_ROT_90:
+ if (info->trim)
+ trim_right_edge(info, srcinfo->image_height);
+ /* Need workspace arrays having transposed dimensions. */
+ need_workspace = TRUE;
+ transpose_it = TRUE;
+ break;
+ case JXFORM_ROT_180:
+ if (info->trim) {
+ trim_right_edge(info, srcinfo->image_width);
+ trim_bottom_edge(info, srcinfo->image_height);
+ }
+ /* Need workspace arrays having same dimensions as source image. */
+ need_workspace = TRUE;
+ break;
+ case JXFORM_ROT_270:
+ if (info->trim)
+ trim_bottom_edge(info, srcinfo->image_width);
+ /* Need workspace arrays having transposed dimensions. */
+ need_workspace = TRUE;
+ transpose_it = TRUE;
+ break;
+ }
+
+ /* Allocate workspace if needed.
+ * Note that we allocate arrays padded out to the next iMCU boundary,
+ * so that transform routines need not worry about missing edge blocks.
+ */
+ if (need_workspace) {
+ coef_arrays = (jvirt_barray_ptr *)
+ (*srcinfo->mem->alloc_small) ((j_common_ptr) srcinfo, JPOOL_IMAGE,
+ SIZEOF(jvirt_barray_ptr) * info->num_components);
+ width_in_iMCUs = (JDIMENSION)
+ jdiv_round_up((long) info->output_width,
+ (long) (info->max_h_samp_factor * DCTSIZE));
+ height_in_iMCUs = (JDIMENSION)
+ jdiv_round_up((long) info->output_height,
+ (long) (info->max_v_samp_factor * DCTSIZE));
+ for (ci = 0; ci < info->num_components; ci++) {
+ compptr = srcinfo->comp_info + ci;
+ if (info->num_components == 1) {
+ /* we're going to force samp factors to 1x1 in this case */
+ h_samp_factor = v_samp_factor = 1;
+ } else if (transpose_it) {
+ h_samp_factor = compptr->v_samp_factor;
+ v_samp_factor = compptr->h_samp_factor;
+ } else {
+ h_samp_factor = compptr->h_samp_factor;
+ v_samp_factor = compptr->v_samp_factor;
+ }
+ width_in_blocks = width_in_iMCUs * h_samp_factor;
+ height_in_blocks = height_in_iMCUs * v_samp_factor;
+ coef_arrays[ci] = (*srcinfo->mem->request_virt_barray)
+ ((j_common_ptr) srcinfo, JPOOL_IMAGE, FALSE,
+ width_in_blocks, height_in_blocks, (JDIMENSION) v_samp_factor);
+ }
+ }
+
+ info->workspace_coef_arrays = coef_arrays;
+}
+
+
+/* Transpose destination image parameters */
+
+LOCAL(void)
+transpose_critical_parameters (j_compress_ptr dstinfo)
+{
+ int tblno, i, j, ci, itemp;
+ jpeg_component_info *compptr;
+ JQUANT_TBL *qtblptr;
+ UINT16 qtemp;
+
+ /* Transpose sampling factors */
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+ itemp = compptr->h_samp_factor;
+ compptr->h_samp_factor = compptr->v_samp_factor;
+ compptr->v_samp_factor = itemp;
+ }
+
+ /* Transpose quantization tables */
+ for (tblno = 0; tblno < NUM_QUANT_TBLS; tblno++) {
+ qtblptr = dstinfo->quant_tbl_ptrs[tblno];
+ if (qtblptr != NULL) {
+ for (i = 0; i < DCTSIZE; i++) {
+ for (j = 0; j < i; j++) {
+ qtemp = qtblptr->quantval[i*DCTSIZE+j];
+ qtblptr->quantval[i*DCTSIZE+j] = qtblptr->quantval[j*DCTSIZE+i];
+ qtblptr->quantval[j*DCTSIZE+i] = qtemp;
+ }
+ }
+ }
+ }
+}
+
+
+/* Adjust Exif image parameters.
+ *
+ * We try to adjust the Tags ExifImageWidth and ExifImageHeight if possible.
+ */
+
+LOCAL(void)
+adjust_exif_parameters (JOCTET FAR * data, unsigned int length,
+ JDIMENSION new_width, JDIMENSION new_height)
+{
+ boolean is_motorola; /* Flag for byte order */
+ unsigned int number_of_tags, tagnum;
+ unsigned int firstoffset, offset;
+ JDIMENSION new_value;
+
+ if (length < 12) return; /* Length of an IFD entry */
+
+ /* Discover byte order */
+ if (GETJOCTET(data[0]) == 0x49 && GETJOCTET(data[1]) == 0x49)
+ is_motorola = FALSE;
+ else if (GETJOCTET(data[0]) == 0x4D && GETJOCTET(data[1]) == 0x4D)
+ is_motorola = TRUE;
+ else
+ return;
+
+ /* Check Tag Mark */
+ if (is_motorola) {
+ if (GETJOCTET(data[2]) != 0) return;
+ if (GETJOCTET(data[3]) != 0x2A) return;
+ } else {
+ if (GETJOCTET(data[3]) != 0) return;
+ if (GETJOCTET(data[2]) != 0x2A) return;
+ }
+
+ /* Get first IFD offset (offset to IFD0) */
+ if (is_motorola) {
+ if (GETJOCTET(data[4]) != 0) return;
+ if (GETJOCTET(data[5]) != 0) return;
+ firstoffset = GETJOCTET(data[6]);
+ firstoffset <<= 8;
+ firstoffset += GETJOCTET(data[7]);
+ } else {
+ if (GETJOCTET(data[7]) != 0) return;
+ if (GETJOCTET(data[6]) != 0) return;
+ firstoffset = GETJOCTET(data[5]);
+ firstoffset <<= 8;
+ firstoffset += GETJOCTET(data[4]);
+ }
+ if (firstoffset > length - 2) return; /* check end of data segment */
+
+ /* Get the number of directory entries contained in this IFD */
+ if (is_motorola) {
+ number_of_tags = GETJOCTET(data[firstoffset]);
+ number_of_tags <<= 8;
+ number_of_tags += GETJOCTET(data[firstoffset+1]);
+ } else {
+ number_of_tags = GETJOCTET(data[firstoffset+1]);
+ number_of_tags <<= 8;
+ number_of_tags += GETJOCTET(data[firstoffset]);
+ }
+ if (number_of_tags == 0) return;
+ firstoffset += 2;
+
+ /* Search for ExifSubIFD offset Tag in IFD0 */
+ for (;;) {
+ if (firstoffset > length - 12) return; /* check end of data segment */
+ /* Get Tag number */
+ if (is_motorola) {
+ tagnum = GETJOCTET(data[firstoffset]);
+ tagnum <<= 8;
+ tagnum += GETJOCTET(data[firstoffset+1]);
+ } else {
+ tagnum = GETJOCTET(data[firstoffset+1]);
+ tagnum <<= 8;
+ tagnum += GETJOCTET(data[firstoffset]);
+ }
+ if (tagnum == 0x8769) break; /* found ExifSubIFD offset Tag */
+ if (--number_of_tags == 0) return;
+ firstoffset += 12;
+ }
+
+ /* Get the ExifSubIFD offset */
+ if (is_motorola) {
+ if (GETJOCTET(data[firstoffset+8]) != 0) return;
+ if (GETJOCTET(data[firstoffset+9]) != 0) return;
+ offset = GETJOCTET(data[firstoffset+10]);
+ offset <<= 8;
+ offset += GETJOCTET(data[firstoffset+11]);
+ } else {
+ if (GETJOCTET(data[firstoffset+11]) != 0) return;
+ if (GETJOCTET(data[firstoffset+10]) != 0) return;
+ offset = GETJOCTET(data[firstoffset+9]);
+ offset <<= 8;
+ offset += GETJOCTET(data[firstoffset+8]);
+ }
+ if (offset > length - 2) return; /* check end of data segment */
+
+ /* Get the number of directory entries contained in this SubIFD */
+ if (is_motorola) {
+ number_of_tags = GETJOCTET(data[offset]);
+ number_of_tags <<= 8;
+ number_of_tags += GETJOCTET(data[offset+1]);
+ } else {
+ number_of_tags = GETJOCTET(data[offset+1]);
+ number_of_tags <<= 8;
+ number_of_tags += GETJOCTET(data[offset]);
+ }
+ if (number_of_tags < 2) return;
+ offset += 2;
+
+ /* Search for ExifImageWidth and ExifImageHeight Tags in this SubIFD */
+ do {
+ if (offset > length - 12) return; /* check end of data segment */
+ /* Get Tag number */
+ if (is_motorola) {
+ tagnum = GETJOCTET(data[offset]);
+ tagnum <<= 8;
+ tagnum += GETJOCTET(data[offset+1]);
+ } else {
+ tagnum = GETJOCTET(data[offset+1]);
+ tagnum <<= 8;
+ tagnum += GETJOCTET(data[offset]);
+ }
+ if (tagnum == 0xA002 || tagnum == 0xA003) {
+ if (tagnum == 0xA002)
+ new_value = new_width; /* ExifImageWidth Tag */
+ else
+ new_value = new_height; /* ExifImageHeight Tag */
+ if (is_motorola) {
+ data[offset+2] = 0; /* Format = unsigned long (4 octets) */
+ data[offset+3] = 4;
+ data[offset+4] = 0; /* Number Of Components = 1 */
+ data[offset+5] = 0;
+ data[offset+6] = 0;
+ data[offset+7] = 1;
+ data[offset+8] = 0;
+ data[offset+9] = 0;
+ data[offset+10] = (JOCTET)((new_value >> 8) & 0xFF);
+ data[offset+11] = (JOCTET)(new_value & 0xFF);
+ } else {
+ data[offset+2] = 4; /* Format = unsigned long (4 octets) */
+ data[offset+3] = 0;
+ data[offset+4] = 1; /* Number Of Components = 1 */
+ data[offset+5] = 0;
+ data[offset+6] = 0;
+ data[offset+7] = 0;
+ data[offset+8] = (JOCTET)(new_value & 0xFF);
+ data[offset+9] = (JOCTET)((new_value >> 8) & 0xFF);
+ data[offset+10] = 0;
+ data[offset+11] = 0;
+ }
+ }
+ offset += 12;
+ } while (--number_of_tags);
+}
+
+
+/* Adjust output image parameters as needed.
+ *
+ * This must be called after jpeg_copy_critical_parameters()
+ * and before jpeg_write_coefficients().
+ *
+ * The return value is the set of virtual coefficient arrays to be written
+ * (either the ones allocated by jtransform_request_workspace, or the
+ * original source data arrays). The caller will need to pass this value
+ * to jpeg_write_coefficients().
+ */
+
+GLOBAL(jvirt_barray_ptr *)
+jtransform_adjust_parameters (j_decompress_ptr srcinfo,
+ j_compress_ptr dstinfo,
+ jvirt_barray_ptr *src_coef_arrays,
+ jpeg_transform_info *info)
+{
+ /* If force-to-grayscale is requested, adjust destination parameters */
+ if (info->force_grayscale) {
+ /* First, ensure we have YCbCr or grayscale data, and that the source's
+ * Y channel is full resolution. (No reasonable person would make Y
+ * be less than full resolution, so actually coping with that case
+ * isn't worth extra code space. But we check it to avoid crashing.)
+ */
+ if (((dstinfo->jpeg_color_space == JCS_YCbCr &&
+ dstinfo->num_components == 3) ||
+ (dstinfo->jpeg_color_space == JCS_GRAYSCALE &&
+ dstinfo->num_components == 1)) &&
+ srcinfo->comp_info[0].h_samp_factor == srcinfo->max_h_samp_factor &&
+ srcinfo->comp_info[0].v_samp_factor == srcinfo->max_v_samp_factor) {
+ /* We use jpeg_set_colorspace to make sure subsidiary settings get fixed
+ * properly. Among other things, it sets the target h_samp_factor &
+ * v_samp_factor to 1, which typically won't match the source.
+ * We have to preserve the source's quantization table number, however.
+ */
+ int sv_quant_tbl_no = dstinfo->comp_info[0].quant_tbl_no;
+ jpeg_set_colorspace(dstinfo, JCS_GRAYSCALE);
+ dstinfo->comp_info[0].quant_tbl_no = sv_quant_tbl_no;
+ } else {
+ /* Sorry, can't do it */
+ ERREXIT(dstinfo, JERR_CONVERSION_NOTIMPL);
+ }
+ } else if (info->num_components == 1) {
+ /* For a single-component source, we force the destination sampling factors
+ * to 1x1, with or without force_grayscale. This is useful because some
+ * decoders choke on grayscale images with other sampling factors.
+ */
+ dstinfo->comp_info[0].h_samp_factor = 1;
+ dstinfo->comp_info[0].v_samp_factor = 1;
+ }
+
+ /* Correct the destination's image dimensions as necessary
+ * for crop and rotate/flip operations.
+ */
+ dstinfo->image_width = info->output_width;
+ dstinfo->image_height = info->output_height;
+
+ /* Transpose destination image parameters */
+ switch (info->transform) {
+ case JXFORM_TRANSPOSE:
+ case JXFORM_TRANSVERSE:
+ case JXFORM_ROT_90:
+ case JXFORM_ROT_270:
+ transpose_critical_parameters(dstinfo);
+ break;
+ }
+
+ /* Adjust Exif properties */
+ if (srcinfo->marker_list != NULL &&
+ srcinfo->marker_list->marker == JPEG_APP0+1 &&
+ srcinfo->marker_list->data_length >= 6 &&
+ GETJOCTET(srcinfo->marker_list->data[0]) == 0x45 &&
+ GETJOCTET(srcinfo->marker_list->data[1]) == 0x78 &&
+ GETJOCTET(srcinfo->marker_list->data[2]) == 0x69 &&
+ GETJOCTET(srcinfo->marker_list->data[3]) == 0x66 &&
+ GETJOCTET(srcinfo->marker_list->data[4]) == 0 &&
+ GETJOCTET(srcinfo->marker_list->data[5]) == 0) {
+ /* Suppress output of JFIF marker */
+ dstinfo->write_JFIF_header = FALSE;
+ /* Adjust Exif image parameters */
+ if (dstinfo->image_width != srcinfo->image_width ||
+ dstinfo->image_height != srcinfo->image_height)
+ /* Align data segment to start of TIFF structure for parsing */
+ adjust_exif_parameters(srcinfo->marker_list->data + 6,
+ srcinfo->marker_list->data_length - 6,
+ dstinfo->image_width, dstinfo->image_height);
+ }
+
+ /* Return the appropriate output data set */
+ if (info->workspace_coef_arrays != NULL)
+ return info->workspace_coef_arrays;
+ return src_coef_arrays;
+}
+
+
+/* Execute the actual transformation, if any.
+ *
+ * This must be called *after* jpeg_write_coefficients, because it depends
+ * on jpeg_write_coefficients to have computed subsidiary values such as
+ * the per-component width and height fields in the destination object.
+ *
+ * Note that some transformations will modify the source data arrays!
+ */
+
+GLOBAL(void)
+jtransform_execute_transform (j_decompress_ptr srcinfo,
+ j_compress_ptr dstinfo,
+ jvirt_barray_ptr *src_coef_arrays,
+ jpeg_transform_info *info)
+{
+ jvirt_barray_ptr *dst_coef_arrays = info->workspace_coef_arrays;
+
+ /* Note: conditions tested here should match those in switch statement
+ * in jtransform_request_workspace()
+ */
+ switch (info->transform) {
+ case JXFORM_NONE:
+ if (info->x_crop_offset != 0 || info->y_crop_offset != 0)
+ do_crop(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
+ src_coef_arrays, dst_coef_arrays);
+ break;
+ case JXFORM_FLIP_H:
+ if (info->y_crop_offset != 0)
+ do_flip_h(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
+ src_coef_arrays, dst_coef_arrays);
+ else
+ do_flip_h_no_crop(srcinfo, dstinfo, info->x_crop_offset,
+ src_coef_arrays);
+ break;
+ case JXFORM_FLIP_V:
+ do_flip_v(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
+ src_coef_arrays, dst_coef_arrays);
+ break;
+ case JXFORM_TRANSPOSE:
+ do_transpose(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
+ src_coef_arrays, dst_coef_arrays);
+ break;
+ case JXFORM_TRANSVERSE:
+ do_transverse(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
+ src_coef_arrays, dst_coef_arrays);
+ break;
+ case JXFORM_ROT_90:
+ do_rot_90(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
+ src_coef_arrays, dst_coef_arrays);
+ break;
+ case JXFORM_ROT_180:
+ do_rot_180(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
+ src_coef_arrays, dst_coef_arrays);
+ break;
+ case JXFORM_ROT_270:
+ do_rot_270(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
+ src_coef_arrays, dst_coef_arrays);
+ break;
+ }
+}
+
+/* jtransform_perfect_transform
+ *
+ * Determine whether lossless transformation is perfectly
+ * possible for a specified image and transformation.
+ *
+ * Inputs:
+ * image_width, image_height: source image dimensions.
+ * MCU_width, MCU_height: pixel dimensions of MCU.
+ * transform: transformation identifier.
+ * Parameter sources from initialized jpeg_struct
+ * (after reading source header):
+ * image_width = cinfo.image_width
+ * image_height = cinfo.image_height
+ * MCU_width = cinfo.max_h_samp_factor * DCTSIZE
+ * MCU_height = cinfo.max_v_samp_factor * DCTSIZE
+ * Result:
+ * TRUE = perfect transformation possible
+ * FALSE = perfect transformation not possible
+ * (may use custom action then)
+ */
+
+GLOBAL(boolean)
+jtransform_perfect_transform(JDIMENSION image_width, JDIMENSION image_height,
+ int MCU_width, int MCU_height,
+ JXFORM_CODE transform)
+{
+ boolean result = TRUE; /* initialize TRUE */
+
+ switch (transform) {
+ case JXFORM_FLIP_H:
+ case JXFORM_ROT_270:
+ if (image_width % (JDIMENSION) MCU_width)
+ result = FALSE;
+ break;
+ case JXFORM_FLIP_V:
+ case JXFORM_ROT_90:
+ if (image_height % (JDIMENSION) MCU_height)
+ result = FALSE;
+ break;
+ case JXFORM_TRANSVERSE:
+ case JXFORM_ROT_180:
+ if (image_width % (JDIMENSION) MCU_width)
+ result = FALSE;
+ if (image_height % (JDIMENSION) MCU_height)
+ result = FALSE;
+ break;
+ }
+
+ return result;
+}
+
+#endif /* TRANSFORMS_SUPPORTED */
+
+
+/* Setup decompression object to save desired markers in memory.
+ * This must be called before jpeg_read_header() to have the desired effect.
+ */
+
+GLOBAL(void)
+jcopy_markers_setup (j_decompress_ptr srcinfo, JCOPY_OPTION option)
+{
+#ifdef SAVE_MARKERS_SUPPORTED
+ int m;
+
+ /* Save comments except under NONE option */
+ if (option != JCOPYOPT_NONE) {
+ jpeg_save_markers(srcinfo, JPEG_COM, 0xFFFF);
+ }
+ /* Save all types of APPn markers iff ALL option */
+ if (option == JCOPYOPT_ALL) {
+ for (m = 0; m < 16; m++)
+ jpeg_save_markers(srcinfo, JPEG_APP0 + m, 0xFFFF);
+ }
+#endif /* SAVE_MARKERS_SUPPORTED */
+}
+
+/* Copy markers saved in the given source object to the destination object.
+ * This should be called just after jpeg_start_compress() or
+ * jpeg_write_coefficients().
+ * Note that those routines will have written the SOI, and also the
+ * JFIF APP0 or Adobe APP14 markers if selected.
+ */
+
+GLOBAL(void)
+jcopy_markers_execute (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
+ JCOPY_OPTION option)
+{
+ jpeg_saved_marker_ptr marker;
+
+ /* In the current implementation, we don't actually need to examine the
+ * option flag here; we just copy everything that got saved.
+ * But to avoid confusion, we do not output JFIF and Adobe APP14 markers
+ * if the encoder library already wrote one.
+ */
+ for (marker = srcinfo->marker_list; marker != NULL; marker = marker->next) {
+ if (dstinfo->write_JFIF_header &&
+ marker->marker == JPEG_APP0 &&
+ marker->data_length >= 5 &&
+ GETJOCTET(marker->data[0]) == 0x4A &&
+ GETJOCTET(marker->data[1]) == 0x46 &&
+ GETJOCTET(marker->data[2]) == 0x49 &&
+ GETJOCTET(marker->data[3]) == 0x46 &&
+ GETJOCTET(marker->data[4]) == 0)
+ continue; /* reject duplicate JFIF */
+ if (dstinfo->write_Adobe_marker &&
+ marker->marker == JPEG_APP0+14 &&
+ marker->data_length >= 5 &&
+ GETJOCTET(marker->data[0]) == 0x41 &&
+ GETJOCTET(marker->data[1]) == 0x64 &&
+ GETJOCTET(marker->data[2]) == 0x6F &&
+ GETJOCTET(marker->data[3]) == 0x62 &&
+ GETJOCTET(marker->data[4]) == 0x65)
+ continue; /* reject duplicate Adobe */
+#ifdef NEED_FAR_POINTERS
+ /* We could use jpeg_write_marker if the data weren't FAR... */
+ {
+ unsigned int i;
+ jpeg_write_m_header(dstinfo, marker->marker, marker->data_length);
+ for (i = 0; i < marker->data_length; i++)
+ jpeg_write_m_byte(dstinfo, marker->data[i]);
+ }
+#else
+ jpeg_write_marker(dstinfo, marker->marker,
+ marker->data, marker->data_length);
+#endif
+ }
+}
projects / opencv / blobdiff