Drop code that attempts to decode frames that are prefixed by junk,

it does too often end up decoding random data into noise without
detecting it. (for example after seeking of some mp3 data with oddly
often occuring startcode emulation)
fixes issue1154.

git-svn-id: file:///var/local/repositories/ffmpeg/trunk@19302 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

diff --git a/libavcodec/mpegaudiodec.c b/libavcodec/mpegaudiodec.c
index a2158bcb88b99566483ede89b2bdd8389e636156..221941abcc4218110597d1f6c05b7b7aa4c5ccbe 100644 (file)
--- a/libavcodec/mpegaudiodec.c
+++ b/libavcodec/mpegaudiodec.c
@@ -2255,20 +2255,15 @@ static int decode_frame(AVCodecContext * avctx,
     MPADecodeContext *s = avctx->priv_data;
     uint32_t header;
     int out_size;
-    int skipped = 0;
     OUT_INT *out_samples = data;
 
-retry:
     if(buf_size < HEADER_SIZE)
         return -1;
 
     header = AV_RB32(buf);
     if(ff_mpa_check_header(header) < 0){
-        buf++;
-        buf_size--;
-        skipped++;
-        av_log(avctx, AV_LOG_ERROR, "Header missing skipping one byte.\n");
-        goto retry;
+        av_log(avctx, AV_LOG_ERROR, "Header missing\n");
+        return -1;
     }
 
     if (ff_mpegaudio_decode_header((MPADecodeHeader *)s, header) == 1) {
@@ -2297,7 +2292,7 @@ retry:
     }else
         av_log(avctx, AV_LOG_DEBUG, "Error while decoding MPEG audio frame.\n"); //FIXME return -1 / but also return the number of bytes consumed
     s->frame_size = 0;
-    return buf_size + skipped;
+    return buf_size;
 }
 
 static void flush(AVCodecContext *avctx){