Crop parameters are unsigned, having them negative could be bad and lead
[ffmpeg.git] / libavcodec / mpeg4video_parser.c
index 4771ca0..9accc91 100644 (file)
 
 #include "parser.h"
 #include "mpegvideo.h"
+#include "mpeg4video_parser.h"
 
 
+int ff_mpeg4_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size){
+    int vop_found, i;
+    uint32_t state;
+
+    vop_found= pc->frame_start_found;
+    state= pc->state;
+
+    i=0;
+    if(!vop_found){
+        for(i=0; i<buf_size; i++){
+            state= (state<<8) | buf[i];
+            if(state == 0x1B6){
+                i++;
+                vop_found=1;
+                break;
+            }
+        }
+    }
+
+    if(vop_found){
+        /* EOF considered as end of frame */
+        if (buf_size == 0)
+            return 0;
+        for(; i<buf_size; i++){
+            state= (state<<8) | buf[i];
+            if((state&0xFFFFFF00) == 0x100){
+                pc->frame_start_found=0;
+                pc->state=-1;
+                return i-3;
+            }
+        }
+    }
+    pc->frame_start_found= vop_found;
+    pc->state= state;
+    return END_NOT_FOUND;
+}
+
 /* XXX: make it use less memory */
 static int av_mpeg4_decode_header(AVCodecParserContext *s1,
                                   AVCodecContext *avctx,