X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fpngdec.c;h=dd3fe67876ca840493e7807511a07cb10bee4889;hb=0a23067ab41326dfa1da41d18923ea8547a51ff5;hp=70635671c20cc94c6e25275ecd8ed4bc867b3b1c;hpb=ada49f936eaafe12365c7b962355d6dcfbfc4029;p=ffmpeg

diff --git a/libavcodec/pngdec.c b/libavcodec/pngdec.c
index 70635671c20..dd3fe67876c 100644
--- a/libavcodec/pngdec.c
+++ b/libavcodec/pngdec.c
@@ -27,7 +27,7 @@
 #include "png.h"
 
 /* TODO:
- * - add 2, 4 and 16 bit depth support
+ * - add 16 bit depth support
  */
 
 #include <zlib.h>
@@ -57,20 +57,46 @@ static void png_put_interlaced_row(uint8_t *dst, int width,
     dsp_mask = png_pass_dsp_mask[pass];
     switch(bits_per_pixel) {
     case 1:
-        /* we must initialize the line to zero before writing to it */
-        if (pass == 0)
-            memset(dst, 0, (width + 7) >> 3);
         src_x = 0;
         for(x = 0; x < width; x++) {
             j = (x & 7);
             if ((dsp_mask << j) & 0x80) {
                 b = (src[src_x >> 3] >> (7 - (src_x & 7))) & 1;
+                dst[x >> 3] &= 0xFF7F>>j;
                 dst[x >> 3] |= b << (7 - j);
             }
             if ((mask << j) & 0x80)
                 src_x++;
         }
         break;
+    case 2:
+        src_x = 0;
+        for(x = 0; x < width; x++) {
+            int j2 = 2*(x&3);
+            j = (x & 7);
+            if ((dsp_mask << j) & 0x80) {
+                b = (src[src_x >> 2] >> (6 - 2*(src_x & 3))) & 3;
+                dst[x >> 2] &= 0xFF3F>>j2;
+                dst[x >> 2] |= b << (6 - j2);
+            }
+            if ((mask << j) & 0x80)
+                src_x++;
+        }
+        break;
+    case 4:
+        src_x = 0;
+        for(x = 0; x < width; x++) {
+            int j2 = 4*(x&1);
+            j = (x & 7);
+            if ((dsp_mask << j) & 0x80) {
+                b = (src[src_x >> 1] >> (4 - 4*(src_x & 1))) & 15;
+                dst[x >> 1] &= 0xFF0F>>j2;
+                dst[x >> 1] |= b << (4 - j2);
+            }
+            if ((mask << j) & 0x80)
+                src_x++;
+        }
+        break;
     default:
         bpp = bits_per_pixel >> 3;
         d = dst;
@@ -319,6 +345,7 @@ static void png_handle_row(PNGDecContext *s)
             }
             s->y++;
             if (s->y == s->height) {
+                memset(s->last_row, 0, s->row_size);
                 for(;;) {
                     if (s->pass == NB_PASSES - 1) {
                         s->state |= PNG_ALLIMAGE;
@@ -479,7 +506,7 @@ static int decode_frame(AVCodecContext *avctx,
                 if(p->data[0])
                     avctx->release_buffer(avctx, p);
 
-                p->reference= 0;
+                p->reference= 1;
                 if(avctx->get_buffer(avctx, p) < 0){
                     av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
                     goto fail;
@@ -580,6 +607,32 @@ static int decode_frame(AVCodecContext *avctx,
         }
     }
  exit_loop:
+
+    if(s->bits_per_pixel == 2){
+        int i, j;
+        uint8_t *pd = s->current_picture->data[0];
+        for(j=0; j < s->height; j++) {
+            for(i=s->width/4-1; i>=0; i--) {
+                pd[4*i+3]=  pd[i]    &3;
+                pd[4*i+2]= (pd[i]>>2)&3;
+                pd[4*i+1]= (pd[i]>>4)&3;
+                pd[4*i+0]=  pd[i]>>6;
+            }
+            pd += s->image_linesize;
+        }
+    }
+    if(s->bits_per_pixel == 4){
+        int i, j;
+        uint8_t *pd = s->current_picture->data[0];
+        for(j=0; j < s->height; j++) {
+            for(i=s->width/2-1; i>=0; i--) {
+                pd[2*i+1]= pd[i]&15;
+                pd[2*i+0]= pd[i]>>4;
+            }
+            pd += s->image_linesize;
+        }
+    }
+
      /* handle p-frames only if a predecessor frame is available */
      if(s->last_picture->data[0] != NULL) {
          if(!(avpkt->flags & AV_PKT_FLAG_KEY)) {