ref: 2c22eeab4e9a67bb218cb4e03df9ed9bad3b6647
parent: 65a3e8bfeba6213859690722281ca290fe3e7d20
author: root <root@ded80894-8fb9-0310-811b-c03f3676ab4d>
date: Fri Oct 22 18:28:07 EDT 2004
Build an unoptimized version of the refinement template context calculation to assist with debugging. This one doesn't seem to work either. git-svn-id: http://svn.ghostscript.com/jbig2dec/trunk@328 ded80894-8fb9-0310-811b-c03f3676ab4d
--- a/jbig2_refinement.c
+++ b/jbig2_refinement.c
@@ -31,9 +31,7 @@
#include <stddef.h>
#include <string.h> /* memcpy(), memset() */
-#ifdef OUTPUT_PBM
#include <stdio.h>
-#endif
#include "jbig2.h"
#include "jbig2_priv.h"
@@ -53,7 +51,100 @@
"refinement region template 0 NYI");
}
+/* look up a pixel value in an image.
+ returns 0 outside the image frame for the convenience of
+ the template code
+*/
static int
+jbig2_image_get_pixel(Jbig2Image *image, int x, int y)
+{+ const int w = image->width;
+ const int h = image->height;
+ const int byte = (x >> 3) + y*image->stride;
+ const int bit = x & 7;
+
+ if ((x < 0) || (x > w)) return 0;
+ if ((y < 0) || (y > h)) return 0;
+
+ return ((image->data[byte]>>bit) & 1);
+}
+
+static int
+jbig2_image_set_pixel(Jbig2Image *image, int x, int y, bool value)
+{+ const int w = image->width;
+ const int h = image->height;
+ int i, scratch, mask;
+ int bit, byte;
+
+ if ((x < 0) || (x > w)) return 0;
+ if ((y < 0) || (y > h)) return 0;
+
+ fprintf(stderr, "set pixel called for image 0x%x (%d x %d) stride %d\n",
+ image, w, h, image->stride);
+
+ byte = (x >> 3) + y*image->stride;
+ bit = x & 7;
+ mask = (1 << bit) ^ 0xff;
+
+ fprintf(stderr, "set pixel mask for bit %d of byte %d (%d,%d) is 0x%02x\n",
+ bit, byte, x, y, mask);
+
+ scratch = image->data[byte] & mask;
+ image->data[byte] = scratch | (value << bit);
+
+ return 1;
+}
+
+static int
+jbig2_decode_refinement_template1_unopt(Jbig2Ctx *ctx,
+ Jbig2Segment *segment,
+ const Jbig2RefinementRegionParams *params,
+ Jbig2ArithState *as,
+ Jbig2Image *image,
+ Jbig2ArithCx *GB_stats)
+{+ const int GBW = image->width;
+ const int GBH = image->height;
+ const int dx = params->DX;
+ const int dy = params->DY;
+ Jbig2Image *ref = params->reference;
+ uint32_t CONTEXT;
+ int x,y;
+ bool bit;
+
+ for (y = 0; y < GBH; y++) {+ for (x = 0; x < GBH; x++) {+ CONTEXT = 0;
+ CONTEXT |= jbig2_image_get_pixel(image, x - 1, y + 0) << 0;
+ CONTEXT |= jbig2_image_get_pixel(image, x + 1, y - 1) << 1;
+ CONTEXT |= jbig2_image_get_pixel(image, x + 0, y - 1) << 2;
+ CONTEXT |= jbig2_image_get_pixel(image, x - 1, y - 1) << 3;
+ CONTEXT |= jbig2_image_get_pixel(ref, x-dx+1, y-dy+1) << 4;
+ CONTEXT |= jbig2_image_get_pixel(ref, x-dx+0, y-dy+1) << 5;
+ CONTEXT |= jbig2_image_get_pixel(ref, x-dx+1, y-dy+0) << 6;
+ CONTEXT |= jbig2_image_get_pixel(ref, x-dx+0, y-dy+0) << 7;
+ CONTEXT |= jbig2_image_get_pixel(ref, x-dx-1, y-dy+0) << 8;
+ CONTEXT |= jbig2_image_get_pixel(ref, x-dx+0, y-dy-1) << 9;
+ bit = jbig2_arith_decode(as, &GB_stats[CONTEXT]);
+ jbig2_image_set_pixel(image, x, y, bit);
+ }
+ }
+
+ {+ static count = 0;
+ char name[32];
+ snprintf(name, 32, "refin-%d.pbm", count);
+ jbig2_image_write_pbm_file(ref, name);
+ snprintf(name, 32, "refout-%d.pbm", count);
+ jbig2_image_write_pbm_file(image, name);
+ count++;
+ }
+
+ return 0;
+}
+
+static int
jbig2_decode_refinement_template1(Jbig2Ctx *ctx,
Jbig2Segment *segment,
const Jbig2RefinementRegionParams *params,
@@ -65,6 +156,8 @@
const int GBH = image->height;
const int stride = image->stride;
const int refstride = params->reference->stride;
+ const int dx = params->DX;
+ const int dy = params->DY;
byte *grreg_line = (byte *)image->data;
byte *grref_line = (byte *)params->reference->data;
int x,y;
@@ -78,9 +171,9 @@
uint32_t line_m1; /* previous line of the decoded bitmap */
line_m1 = (y >= 1) ? grreg_line[-stride] : 0;
- refline_m1 = (y >= 1) ? grref_line[-stride] << 2: 0;
- refline_0 = grref_line[0] << 4;
- refline_1 = (y < GBW - 1) ? grref_line[+stride] << 7 : 0;
+ refline_m1 = ((y-dy) >= 1) ? grref_line[(-1-dy)*stride] << 2: 0;
+ refline_0 = (((y-dy) > 0) && ((y-dy) < GBH)) ? grref_line[(0-dy)*stride] << 4 : 0;
+ refline_1 = (y < GBW - 1) ? grref_line[(+1-dy)*stride] << 7 : 0;
CONTEXT = ((line_m1 >> 5) & 0x00e) |
((refline_1 >> 5) & 0x030) |
((refline_0 >> 5) & 0x1c0) |
@@ -170,7 +263,7 @@
return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number,
"decode_refinement_region: typical prediction coding NYI");
if (params->GRTEMPLATE)
- return jbig2_decode_refinement_template1(ctx, segment, params,
+ return jbig2_decode_refinement_template1_unopt(ctx, segment, params,
as, image, GB_stats);
else
return jbig2_decode_refinement_template0(ctx, segment, params,