better non conformant divx packed bitstream detection, so unpacked (no b frames) divx MPEG4-ES streams can be read

Originally committed as revision 1695 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/h263.c

@@ -4566,6 +4566,7 @@ static int decode_user_data(MpegEncContext *s, GetBitContext *gb){
     int i;
     int e;
     int ver, build, ver2, ver3;
+    char last;
 
     buf[0]= show_bits(gb, 8);
     for(i=1; i<256; i++){
@@ -4576,14 +4577,19 @@ static int decode_user_data(MpegEncContext *s, GetBitContext *gb){
     buf[255]=0;
 
     /* divx detection */
-    e=sscanf(buf, "DivX%dBuild%d", &ver, &build);
+    e=sscanf(buf, "DivX%dBuild%d%c", &ver, &build, &last);
-    if(e!=2)
+    if(e<2)
-        e=sscanf(buf, "DivX%db%d", &ver, &build);
+        e=sscanf(buf, "DivX%db%d%c", &ver, &build, &last);
-    if(e==2){
+    if(e>=2){
         s->divx_version= ver;
         s->divx_build= build;
+        s->divx_packed= e==3 && last=='p';
         if(s->picture_number==0){
-            printf("This file was encoded with DivX%d Build%d\n", ver, build);
+            printf("This file was encoded with DivX%d Build%d", ver, build);
+            if(s->divx_packed)
+                printf("p\n");
+            else
+                printf("\n");
         }
     }
     

libavcodec/h263dec.c

@@ -128,7 +128,7 @@ int ff_h263_decode_end(AVCodecContext *avctx)
 static int get_consumed_bytes(MpegEncContext *s, int buf_size){
     int pos= (get_bits_count(&s->gb)+7)>>3;
     
-    if(s->divx_version>=500){
+    if(s->divx_packed){
         //we would have to scan through the whole buf to handle the weird reordering ...
         return buf_size; 
     }else if(s->flags&CODEC_FLAG_TRUNCATED){
@@ -675,7 +675,7 @@ retry:
         }
     
     /* divx 5.01+ bistream reorder stuff */
-    if(s->codec_id==CODEC_ID_MPEG4 && s->bitstream_buffer_size==0 && s->divx_version>=500){
+    if(s->codec_id==CODEC_ID_MPEG4 && s->bitstream_buffer_size==0 && s->divx_packed){
         int current_pos= get_bits_count(&s->gb)>>3;
 
         if(   buf_size - current_pos > 5 

libavcodec/mpegvideo.h

@@ -499,6 +499,7 @@ typedef struct MpegEncContext {
     /* divx specific, used to workaround (many) bugs in divx5 */
     int divx_version;
     int divx_build;
+    int divx_packed;
 #define BITSTREAM_BUFFER_SIZE 1024*256
     uint8_t *bitstream_buffer; //Divx 5.01 puts several frames in a single one, this is used to reorder them
     int bitstream_buffer_size;