Add a new libjpeg API function (jpeg_skip_scanlines()) to allow for partially decoding a JPEG image.
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1582 632fc199-4ca6-4c93-a231-07263d6284db
diff --git a/jdmainct.c b/jdmainct.c
index 7f7bd33..e4ba1c4 100644
--- a/jdmainct.c
+++ b/jdmainct.c
@@ -15,10 +15,7 @@
* supplies the equivalent of the main buffer in that case.
*/
-#define JPEG_INTERNALS
-#include "jinclude.h"
-#include "jpeglib.h"
-#include "jpegcomp.h"
+#include "jdmainct.h"
/*
@@ -112,36 +109,6 @@
*/
-/* Private buffer controller object */
-
-typedef struct {
- struct jpeg_d_main_controller pub; /* public fields */
-
- /* Pointer to allocated workspace (M or M+2 row groups). */
- JSAMPARRAY buffer[MAX_COMPONENTS];
-
- boolean buffer_full; /* Have we gotten an iMCU row from decoder? */
- JDIMENSION rowgroup_ctr; /* counts row groups output to postprocessor */
-
- /* Remaining fields are only used in the context case. */
-
- /* These are the master pointers to the funny-order pointer lists. */
- JSAMPIMAGE xbuffer[2]; /* pointers to weird pointer lists */
-
- int whichptr; /* indicates which pointer set is now in use */
- int context_state; /* process_data state machine status */
- JDIMENSION rowgroups_avail; /* row groups available to postprocessor */
- JDIMENSION iMCU_row_ctr; /* counts iMCU rows to detect image top/bot */
-} my_main_controller;
-
-typedef my_main_controller * my_main_ptr;
-
-/* context_state values: */
-#define CTX_PREPARE_FOR_IMCU 0 /* need to prepare for MCU row */
-#define CTX_PROCESS_IMCU 1 /* feeding iMCU to postprocessor */
-#define CTX_POSTPONED_ROW 2 /* feeding postponed row group */
-
-
/* Forward declarations */
METHODDEF(void) process_data_simple_main
(j_decompress_ptr cinfo, JSAMPARRAY output_buf,
@@ -238,34 +205,6 @@
LOCAL(void)
-set_wraparound_pointers (j_decompress_ptr cinfo)
-/* Set up the "wraparound" pointers at top and bottom of the pointer lists.
- * This changes the pointer list state from top-of-image to the normal state.
- */
-{
- my_main_ptr main_ptr = (my_main_ptr) cinfo->main;
- int ci, i, rgroup;
- int M = cinfo->_min_DCT_scaled_size;
- jpeg_component_info *compptr;
- JSAMPARRAY xbuf0, xbuf1;
-
- for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
- ci++, compptr++) {
- rgroup = (compptr->v_samp_factor * compptr->_DCT_scaled_size) /
- cinfo->_min_DCT_scaled_size; /* height of a row group of component */
- xbuf0 = main_ptr->xbuffer[0][ci];
- xbuf1 = main_ptr->xbuffer[1][ci];
- for (i = 0; i < rgroup; i++) {
- xbuf0[i - rgroup] = xbuf0[rgroup*(M+1) + i];
- xbuf1[i - rgroup] = xbuf1[rgroup*(M+1) + i];
- xbuf0[rgroup*(M+2) + i] = xbuf0[i];
- xbuf1[rgroup*(M+2) + i] = xbuf1[i];
- }
- }
-}
-
-
-LOCAL(void)
set_bottom_pointers (j_decompress_ptr cinfo)
/* Change the pointer lists to duplicate the last sample row at the bottom
* of the image. whichptr indicates which xbuffer holds the final iMCU row.