fixed un-premultiply routines

[swftools.git] / lib / modules / swfbits.c

diff --git a/lib/modules/swfbits.c b/lib/modules/swfbits.c
index f238503..0af32c7 100644 (file)
--- a/lib/modules/swfbits.c
+++ b/lib/modules/swfbits.c
@@ -37,6 +37,30 @@ int swf_ImageHasAlpha(RGBA*img, int width, int height)
     return hasalpha;
 }
 
+int swf_ImageGetNumberOfPaletteEntries2(RGBA*_img, int width, int height)
+{
+    int len = width*height;
+    int t;
+    U32* img = (U32*)_img;
+    U32 color1 = img[0];
+    U32 color2 = 0;
+    for(t=1;t<len;t++) {
+       if(img[t] != color1) {
+           color2 = img[t];
+           break;
+       }
+    }
+    if(t==len)
+       return 1;
+
+    for(;t<len;t++) {
+       if(img[t] != color1 && img[t] != color2) {
+           return width*height;
+       }
+    }
+    return 2;
+}
+
 /*int swf_ImageGetNumberOfPaletteEntries(RGBA*img, int width, int height, RGBA*palette)
 {
     int len = width*height;
@@ -126,8 +150,10 @@ int swf_ImageGetNumberOfPaletteEntries(RGBA*img, int width, int height, RGBA*pal
        }
        lastcol32 = col32;
     }
-    if(palette_overflow)
+    if(palette_overflow) {
+       free(pal);
        return width*height;
+    }
     if(palette) {
        int i = 0;
        for(t=0;t<256;t++) {
@@ -378,7 +404,11 @@ int swf_SetJPEGBits(TAG * t, char *fname, int quality)
 static void tag_init_source(struct jpeg_decompress_struct *cinfo)
 {
     TAG *tag = (TAG *) cinfo->client_data;
-    swf_SetTagPos(tag, 2);
+    if (tag->id == ST_DEFINEBITSJPEG3) {
+       swf_SetTagPos(tag, 6);
+    } else {
+       swf_SetTagPos(tag, 2);
+    }
     cinfo->src->bytes_in_buffer = 0;
 }
 static boolean tag_fill_input_buffer(struct jpeg_decompress_struct *cinfo)
@@ -424,16 +454,22 @@ RGBA *swf_JPEG2TagToImage(TAG * tag, int *width, int *height)
     int y;
     *width = 0;
     *height = 0;
+    int offset = 0;
+    int oldtaglen = 0;
 
     if (tag->id == ST_DEFINEBITSJPEG) {
-       fprintf(stderr,
-               "rfxswf: extracting from definebitsjpeg not yet supported");
+       fprintf(stderr, "rfxswf: extracting from definebitsjpeg not yet supported\n");
        return 0;
     }
     if (tag->id == ST_DEFINEBITSJPEG3) {
-       fprintf(stderr,
-               "rfxswf: extracting from definebitsjpeg3 not yet supported");
+#ifdef HAVE_ZLIB
+       offset = swf_GetU32(tag);
+       oldtaglen = tag->len;
+       tag->len = offset+6;
+#else
+       fprintf(stderr, "rfxswf: extracting from definebitsjpeg3 not possible: no zlib\n");
        return 0;
+#endif
     }
 
     cinfo.err = jpeg_std_error(&jerr);
@@ -474,6 +510,30 @@ RGBA *swf_JPEG2TagToImage(TAG * tag, int *width, int *height)
     jpeg_finish_decompress(&cinfo);
 
     jpeg_destroy_decompress(&cinfo);
+
+#ifdef HAVE_ZLIB
+    if(offset) {
+       U32 datalen = cinfo.output_width*cinfo.output_height;
+       U8* alphadata = (U8*)rfx_alloc(datalen);
+       int error;
+       tag->len = oldtaglen;
+       swf_SetTagPos(tag, 6+offset);
+       error = uncompress(alphadata, &datalen, &tag->data[tag->pos], tag->len - tag->pos);
+       if (error != Z_OK) {
+           fprintf(stderr, "rfxswf: Zlib error %d while extracting definejpeg3\n", error);
+           return 0;
+       }
+       for(y=0;y<cinfo.output_height;y++) {
+           RGBA*line = &dest[y*cinfo.output_width];
+           U8*aline = &alphadata[y*cinfo.output_width];
+           int x;
+           for(x=0;x<cinfo.output_width;x++) {
+               line[x].a = aline[x];
+           }
+       }
+       free(alphadata);
+    }
+#endif
     return dest;
 }
 
@@ -683,6 +743,17 @@ int swf_SetLosslessBitsGrayscale(TAG * t, U16 width, U16 height, U8 * bitmap)
     return swf_SetLosslessBitsIndexed(t, width, height, bitmap, NULL, 256);
 }
 
+void swf_PreMultiplyAlpha(RGBA*data, int width, int height)
+{
+    int num = width*height;
+    int t;
+    for(t=0;t<num;t++) {
+       data[t].r = ((int)data[t].r*data[t].a)/255;
+       data[t].g = ((int)data[t].g*data[t].a)/255;
+       data[t].b = ((int)data[t].b*data[t].a)/255;
+    }
+}
+
 void swf_SetLosslessImage(TAG*tag, RGBA*data, int width, int height)
 {
     int hasalpha = swf_ImageHasAlpha(data, width, height);
@@ -691,7 +762,7 @@ void swf_SetLosslessImage(TAG*tag, RGBA*data, int width, int height)
        tag->id = ST_DEFINEBITSLOSSLESS;
     } else {
        tag->id = ST_DEFINEBITSLOSSLESS2;
-       /* TODO: premultiply alpha? */
+       swf_PreMultiplyAlpha(data, width, height);
     }
     num = swf_ImageGetNumberOfPaletteEntries(data, width, height, 0);
     if(num>1 && num<=256) {
@@ -801,6 +872,8 @@ RGBA *swf_DefineLosslessBitsTagToImage(TAG * tag, int *dwidth, int *dheight)
            palette[t].b = data[pos++];
            if (alpha) {
                palette[t].a = data[pos++];
+           } else {
+               palette[t].a = 255;
            }
        }
     }
@@ -820,10 +893,20 @@ RGBA *swf_DefineLosslessBitsTagToImage(TAG * tag, int *dwidth, int *dheight)
                }
            } else {
                for (x = 0; x < width; x++) {
-                   /* TODO: un-premultiply alpha? */
-                   dest[pos2].r = data[pos + 1];
-                   dest[pos2].g = data[pos + 2];
-                   dest[pos2].b = data[pos + 3];
+                   /* TODO: is un-premultiplying alpha the right thing to do?
+                      dest[pos2].r = data[pos + 1];
+                      dest[pos2].g = data[pos + 2];
+                      dest[pos2].b = data[pos + 3];*/
+                   int alpha = data[pos+0];
+                   if(alpha) {
+                       dest[pos2].r = ((int)data[pos + 1]*255)/alpha;
+                       dest[pos2].g = ((int)data[pos + 2]*255)/alpha;
+                       dest[pos2].b = ((int)data[pos + 3]*255)/alpha;
+                   } else {
+                       dest[pos2].r = data[pos + 1];
+                       dest[pos2].g = data[pos + 2];
+                       dest[pos2].b = data[pos + 3];
+                   }
                    dest[pos2].a = data[pos + 0];       //alpha
                    pos2++;
                    pos += 4;
@@ -970,6 +1053,9 @@ TAG* swf_AddImage(TAG*tag, int bitid, RGBA*mem, int width, int height, int quali
 RGBA *swf_ExtractImage(TAG * tag, int *dwidth, int *dheight)
 {
     RGBA *img;
+    
+    swf_SetTagPos(tag, 2); // id is 2 bytes
+
     if (tag->id == ST_DEFINEBITSJPEG ||
        tag->id == ST_DEFINEBITSJPEG2 || tag->id == ST_DEFINEBITSJPEG3) {
 #ifdef HAVE_JPEGLIB
@@ -1013,12 +1099,13 @@ void swf_RemoveJPEGTables(SWF * swf)
     tag = swf->firstTag;
     while (tag) {
        if (tag->id == ST_DEFINEBITSJPEG) {
-           void *data = rfx_alloc(tag->len);
+           int len = tag->len;
+           void *data = rfx_alloc(len);
            swf_GetBlock(tag, data, tag->len);
            swf_ResetTag(tag, ST_DEFINEBITSJPEG2);
            swf_SetBlock(tag, &((U8*)data)[0], 2); //id
            swf_SetBlock(tag, tables_tag->data, tables_tag->len);
-           swf_SetBlock(tag, &((U8*)data)[2], tag->len-2);
+           swf_SetBlock(tag, &((U8*)data)[2], len-2);
            free(data);
        }
        tag = tag->next;
@@ -1091,7 +1178,6 @@ static scale_lookup_t**make_scale_lookup(int width, int newwidth)
     lblockx[newwidth] = p_x;
     return lblockx;
 }
-
 RGBA* swf_ImageScale(RGBA*data, int width, int height, int newwidth, int newheight)
 {
     int x,y;
@@ -1102,6 +1188,12 @@ RGBA* swf_ImageScale(RGBA*data, int width, int height, int newwidth, int newheig
     if(newwidth<1 || newheight<1)
        return 0;
 
+    /* this is bad because this scaler doesn't yet handle monochrome
+       images with 2 colors in a way that the final image hasn't more
+       than 256 colors */
+    if(swf_ImageGetNumberOfPaletteEntries2(data, width, height) == 2)
+       fprintf(stderr, "Warning: scaling monochrome image\n");
+
     tmpline = (rgba_int_t*)malloc(width*sizeof(rgba_int_t));
     newdata = (RGBA*)malloc(newwidth*newheight*sizeof(RGBA));