+++ /dev/null
-/*
- * jcmainct.c
- *
- * Copyright (C) 1994-1996, 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 the main buffer controller for compression.
- * The main buffer lies between the pre-processor and the JPEG
- * compressor proper; it holds downsampled data in the JPEG colorspace.
- */
-
-#define JPEG_INTERNALS
-#include "jinclude.h"
-#include "jpeglib.h"
-
-
-/* Note: currently, there is no operating mode in which a full-image buffer
- * is needed at this step. If there were, that mode could not be used with
- * "raw data" input, since this module is bypassed in that case. However,
- * we've left the code here for possible use in special applications.
- */
-#undef FULL_MAIN_BUFFER_SUPPORTED
-
-
-/* Private buffer controller object */
-
-typedef struct {
- struct jpeg_c_main_controller pub; /* public fields */
-
- JDIMENSION cur_iMCU_row; /* number of current iMCU row */
- JDIMENSION rowgroup_ctr; /* counts row groups received in iMCU row */
- boolean suspended; /* remember if we suspended output */
- J_BUF_MODE pass_mode; /* current operating mode */
-
- /* If using just a strip buffer, this points to the entire set of buffers
- * (we allocate one for each component). In the full-image case, this
- * points to the currently accessible strips of the virtual arrays.
- */
- JSAMPARRAY buffer[MAX_COMPONENTS];
-
-#ifdef FULL_MAIN_BUFFER_SUPPORTED
- /* If using full-image storage, this array holds pointers to virtual-array
- * control blocks for each component. Unused if not full-image storage.
- */
- jvirt_sarray_ptr whole_image[MAX_COMPONENTS];
-#endif
-} my_main_controller;
-
-typedef my_main_controller * my_main_ptr;
-
-
-/* Forward declarations */
-METHODDEF(void) process_data_simple_main
- JPP((j_compress_ptr cinfo, JSAMPARRAY input_buf,
- JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail));
-#ifdef FULL_MAIN_BUFFER_SUPPORTED
-METHODDEF(void) process_data_buffer_main
- JPP((j_compress_ptr cinfo, JSAMPARRAY input_buf,
- JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail));
-#endif
-
-
-/*
- * Initialize for a processing pass.
- */
-
-METHODDEF(void)
-start_pass_main (j_compress_ptr cinfo, J_BUF_MODE pass_mode)
-{
- my_main_ptr main = (my_main_ptr) cinfo->main;
-
- /* Do nothing in raw-data mode. */
- if (cinfo->raw_data_in)
- return;
-
- main->cur_iMCU_row = 0; /* initialize counters */
- main->rowgroup_ctr = 0;
- main->suspended = FALSE;
- main->pass_mode = pass_mode; /* save mode for use by process_data */
-
- switch (pass_mode) {
- case JBUF_PASS_THRU:
-#ifdef FULL_MAIN_BUFFER_SUPPORTED
- if (main->whole_image[0] != NULL)
- ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
-#endif
- main->pub.process_data = process_data_simple_main;
- break;
-#ifdef FULL_MAIN_BUFFER_SUPPORTED
- case JBUF_SAVE_SOURCE:
- case JBUF_CRANK_DEST:
- case JBUF_SAVE_AND_PASS:
- if (main->whole_image[0] == NULL)
- ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
- main->pub.process_data = process_data_buffer_main;
- break;
-#endif
- default:
- ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
- break;
- }
-}
-
-
-/*
- * Process some data.
- * This routine handles the simple pass-through mode,
- * where we have only a strip buffer.
- */
-
-METHODDEF(void)
-process_data_simple_main (j_compress_ptr cinfo,
- JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
- JDIMENSION in_rows_avail)
-{
- my_main_ptr main = (my_main_ptr) cinfo->main;
-
- while (main->cur_iMCU_row < cinfo->total_iMCU_rows) {
- /* Read input data if we haven't filled the main buffer yet */
- if (main->rowgroup_ctr < DCTSIZE)
- (*cinfo->prep->pre_process_data) (cinfo,
- input_buf, in_row_ctr, in_rows_avail,
- main->buffer, &main->rowgroup_ctr,
- (JDIMENSION) DCTSIZE);
-
- /* If we don't have a full iMCU row buffered, return to application for
- * more data. Note that preprocessor will always pad to fill the iMCU row
- * at the bottom of the image.
- */
- if (main->rowgroup_ctr != DCTSIZE)
- return;
-
- /* Send the completed row to the compressor */
- if (! (*cinfo->coef->compress_data) (cinfo, main->buffer)) {
- /* If compressor did not consume the whole row, then we must need to
- * suspend processing and return to the application. In this situation
- * we pretend we didn't yet consume the last input row; otherwise, if
- * it happened to be the last row of the image, the application would
- * think we were done.
- */
- if (! main->suspended) {
- (*in_row_ctr)--;
- main->suspended = TRUE;
- }
- return;
- }
- /* We did finish the row. Undo our little suspension hack if a previous
- * call suspended; then mark the main buffer empty.
- */
- if (main->suspended) {
- (*in_row_ctr)++;
- main->suspended = FALSE;
- }
- main->rowgroup_ctr = 0;
- main->cur_iMCU_row++;
- }
-}
-
-
-#ifdef FULL_MAIN_BUFFER_SUPPORTED
-
-/*
- * Process some data.
- * This routine handles all of the modes that use a full-size buffer.
- */
-
-METHODDEF(void)
-process_data_buffer_main (j_compress_ptr cinfo,
- JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
- JDIMENSION in_rows_avail)
-{
- my_main_ptr main = (my_main_ptr) cinfo->main;
- int ci;
- jpeg_component_info *compptr;
- boolean writing = (main->pass_mode != JBUF_CRANK_DEST);
-
- while (main->cur_iMCU_row < cinfo->total_iMCU_rows) {
- /* Realign the virtual buffers if at the start of an iMCU row. */
- if (main->rowgroup_ctr == 0) {
- for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
- ci++, compptr++) {
- main->buffer[ci] = (*cinfo->mem->access_virt_sarray)
- ((j_common_ptr) cinfo, main->whole_image[ci],
- main->cur_iMCU_row * (compptr->v_samp_factor * DCTSIZE),
- (JDIMENSION) (compptr->v_samp_factor * DCTSIZE), writing);
- }
- /* In a read pass, pretend we just read some source data. */
- if (! writing) {
- *in_row_ctr += cinfo->max_v_samp_factor * DCTSIZE;
- main->rowgroup_ctr = DCTSIZE;
- }
- }
-
- /* If a write pass, read input data until the current iMCU row is full. */
- /* Note: preprocessor will pad if necessary to fill the last iMCU row. */
- if (writing) {
- (*cinfo->prep->pre_process_data) (cinfo,
- input_buf, in_row_ctr, in_rows_avail,
- main->buffer, &main->rowgroup_ctr,
- (JDIMENSION) DCTSIZE);
- /* Return to application if we need more data to fill the iMCU row. */
- if (main->rowgroup_ctr < DCTSIZE)
- return;
- }
-
- /* Emit data, unless this is a sink-only pass. */
- if (main->pass_mode != JBUF_SAVE_SOURCE) {
- if (! (*cinfo->coef->compress_data) (cinfo, main->buffer)) {
- /* If compressor did not consume the whole row, then we must need to
- * suspend processing and return to the application. In this situation
- * we pretend we didn't yet consume the last input row; otherwise, if
- * it happened to be the last row of the image, the application would
- * think we were done.
- */
- if (! main->suspended) {
- (*in_row_ctr)--;
- main->suspended = TRUE;
- }
- return;
- }
- /* We did finish the row. Undo our little suspension hack if a previous
- * call suspended; then mark the main buffer empty.
- */
- if (main->suspended) {
- (*in_row_ctr)++;
- main->suspended = FALSE;
- }
- }
-
- /* If get here, we are done with this iMCU row. Mark buffer empty. */
- main->rowgroup_ctr = 0;
- main->cur_iMCU_row++;
- }
-}
-
-#endif /* FULL_MAIN_BUFFER_SUPPORTED */
-
-
-/*
- * Initialize main buffer controller.
- */
-
-GLOBAL(void)
-jinit_c_main_controller (j_compress_ptr cinfo, boolean need_full_buffer)
-{
- my_main_ptr main;
- int ci;
- jpeg_component_info *compptr;
-
- main = (my_main_ptr)
- (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
- SIZEOF(my_main_controller));
- cinfo->main = (struct jpeg_c_main_controller *) main;
- main->pub.start_pass = start_pass_main;
-
- /* We don't need to create a buffer in raw-data mode. */
- if (cinfo->raw_data_in)
- return;
-
- /* Create the buffer. It holds downsampled data, so each component
- * may be of a different size.
- */
- if (need_full_buffer) {
-#ifdef FULL_MAIN_BUFFER_SUPPORTED
- /* Allocate a full-image virtual array for each component */
- /* Note we pad the bottom to a multiple of the iMCU height */
- for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
- ci++, compptr++) {
- main->whole_image[ci] = (*cinfo->mem->request_virt_sarray)
- ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE,
- compptr->width_in_blocks * DCTSIZE,
- (JDIMENSION) jround_up((long) compptr->height_in_blocks,
- (long) compptr->v_samp_factor) * DCTSIZE,
- (JDIMENSION) (compptr->v_samp_factor * DCTSIZE));
- }
-#else
- ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
-#endif
- } else {
-#ifdef FULL_MAIN_BUFFER_SUPPORTED
- main->whole_image[0] = NULL; /* flag for no virtual arrays */
-#endif
- /* Allocate a strip buffer for each component */
- for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
- ci++, compptr++) {
- main->buffer[ci] = (*cinfo->mem->alloc_sarray)
- ((j_common_ptr) cinfo, JPOOL_IMAGE,
- compptr->width_in_blocks * DCTSIZE,
- (JDIMENSION) (compptr->v_samp_factor * DCTSIZE));
- }
- }
-}
projects / opencv / blobdiff