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-rw-r--r--media/libjpeg/jdmainct.h71
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diff --git a/media/libjpeg/jdmainct.h b/media/libjpeg/jdmainct.h
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+/*
+ * jdmainct.h
+ *
+ * This file was part of the Independent JPEG Group's software:
+ * Copyright (C) 1994-1996, Thomas G. Lane.
+ * For conditions of distribution and use, see the accompanying README.ijg
+ * file.
+ */
+
+#define JPEG_INTERNALS
+#include "jpeglib.h"
+#include "jpegcomp.h"
+
+
+/* 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 */
+
+
+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];
+ }
+ }
+}