jcmainct.cpp File Reference

#include "jinclude.h"
#include "jpeglib.h"

Include dependency graph for jcmainct.cpp:

Classes
struct	my_main_controller

Macros
#define	JPEG_INTERNALS

Typedefs
typedef my_main_controller *	my_main_ptr

Functions
static void	process_data_simple_main (j_compress_ptr cinfo, JSAMPARRAY input_buf, JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail)
static void	start_pass_main (j_compress_ptr cinfo, J_BUF_MODE pass_mode)
void	jinit_c_main_controller (j_compress_ptr cinfo, boolean need_full_buffer)

Macro Definition Documentation

#define JPEG_INTERNALS

Typedef Documentation

typedef my_main_controller* my_main_ptr

Function Documentation

static void process_data_simple_main ( j_compress_ptr  cinfo, JSAMPARRAY  input_buf, JDIMENSION *  in_row_ctr, JDIMENSION  in_rows_avail  )

static

{
  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++;
  }
}

static void start_pass_main ( j_compress_ptr  cinfo, J_BUF_MODE  pass_mode  )

static

{
  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;
  }
}

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));
    }
  }
}