ref: 6f0b0d1802ad565e908adac9601e650bdfb8af94
parent: 7d9a6439364da7ea94311d69f877ae37485fd1f7
author: giles <giles@ded80894-8fb9-0310-811b-c03f3676ab4d>
date: Thu Dec 23 06:54:43 EST 2004
Implement a slow general fallback for image compositing. This adds support for non-OR composition operators. git-svn-id: http://svn.ghostscript.com/jbig2dec/trunk@372 ded80894-8fb9-0310-811b-c03f3676ab4d
--- a/jbig2_image.c
+++ b/jbig2_image.c
@@ -81,6 +81,66 @@
jbig2_free(ctx->allocator, image);
}
+/* composite one jbig2_image onto another
+ slow but general version */
+int jbig2_image_compose_unopt(Jbig2Ctx *ctx,
+ Jbig2Image *dst, Jbig2Image *src,
+ int x, int y, Jbig2ComposeOp op)
+{+ int i, j;
+ int sw = src->width;
+ int sh = src->height;
+ int sx = 0;
+ int sy = 0;
+
+ /* clip to the dst image boundaries */
+ if (x < 0) { sx += -x; sw -= -x; x = 0; }+ if (y < 0) { sy += -y; sh -= -y; y = 0; }+ if (x + sw >= dst->width) sw = dst->width - x;
+ if (y + sh >= dst->height) sh = dst->height - y;
+
+ switch (op) {+ case JBIG2_COMPOSE_OR:
+ for (j = 0; j < sh; j++) {+ for (i = 0; i < sw; i++) {+ jbig2_image_set_pixel(dst, i+x, j+y,
+ jbig2_image_get_pixel(src, i+sx, j+sy) |
+ jbig2_image_get_pixel(dst, i+x, j+y));
+ }
+ }
+ break;
+ case JBIG2_COMPOSE_AND:
+ for (j = 0; j < sh; j++) {+ for (i = 0; i < sw; i++) {+ jbig2_image_set_pixel(dst, i+x, j+y,
+ jbig2_image_get_pixel(src, i+sx, j+sy) &
+ jbig2_image_get_pixel(dst, i+x, j+y));
+ }
+ }
+ break;
+ case JBIG2_COMPOSE_XOR:
+ for (j = 0; j < sh; j++) {+ for (i = 0; i < sw; i++) {+ jbig2_image_set_pixel(dst, i+x, j+y,
+ jbig2_image_get_pixel(src, i+sx, j+sy) ^
+ jbig2_image_get_pixel(dst, i+x, j+y));
+ }
+ }
+ break;
+ case JBIG2_COMPOSE_XNOR:
+ for (j = 0; j < sh; j++) {+ for (i = 0; i < sw; i++) {+ jbig2_image_set_pixel(dst, i+x, j+y,
+ ~(jbig2_image_get_pixel(src, i+sx, j+sy) ^
+ jbig2_image_get_pixel(dst, i+x, j+y)));
+ }
+ }
+ break;
+ }
+
+ return 0;
+}
+
/* composite one jbig2_image onto another */
int jbig2_image_compose(Jbig2Ctx *ctx, Jbig2Image *dst, Jbig2Image *src,
int x, int y, Jbig2ComposeOp op)
@@ -94,8 +154,8 @@
uint8_t mask, rightmask;
if (op != JBIG2_COMPOSE_OR) {- jbig2_error(ctx, JBIG2_SEVERITY_WARNING, -1,
- "non-OR composition modes NYI");
+ /* hand off the the general routine */
+ return jbig2_image_compose_unopt(ctx, dst, src, x, y, op);
}
/* clip */