From 14207b27b5ea61b33092f0d23286b03ed4bcd894 Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michaelni@gmx.at>
Date: Fri, 6 Sep 2002 22:30:16 +0000
Subject: [PATCH] support decoding of the last mpeg "packet" even if no
startcode is immedeatly afterwards (fixes bugs with mpeg in avi) new behavior
is only activated if CODEC_FLAG_NOT_TRUNCATED is set
Originally committed as revision 909 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
libavcodec/avcodec.h | 1 +
libavcodec/mpeg12.c | 18 ++++++++++++++----
2 files changed, 15 insertions(+), 4 deletions(-)
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 619623bb74f..96db4d9031f 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -119,6 +119,7 @@ static const int Motion_Est_QTab[] = { ME_ZERO, ME_PHODS, ME_LOG,
#define CODEC_FLAG_GRAY 0x2000 /* only decode/encode grayscale */
#define CODEC_FLAG_EMU_EDGE 0x4000/* dont draw edges */
#define CODEC_FLAG_DR1 0x8000 /* dr1 */
+#define CODEC_FLAG_NOT_TRUNCATED 0x00010000 /* input bitstream is not truncated, except before a startcode */
/* codec capabilities */
/* decoder can use draw_horiz_band callback */
diff --git a/libavcodec/mpeg12.c b/libavcodec/mpeg12.c
index 97c2e98ccb8..ef6bec7ace7 100644
--- a/libavcodec/mpeg12.c
+++ b/libavcodec/mpeg12.c
@@ -584,7 +584,7 @@ static VLC mb_ptype_vlc;
static VLC mb_btype_vlc;
static VLC mb_pat_vlc;
-void mpeg1_init_vlc(MpegEncContext *s)
+static void init_vlcs(MpegEncContext *s)
{
static int done = 0;
@@ -1260,6 +1260,7 @@ static int mpeg_decode_init(AVCodecContext *avctx)
s->mpeg_enc_ctx.flags= avctx->flags;
common_init(&s->mpeg_enc_ctx);
+ init_vlcs(&s->mpeg_enc_ctx);
s->header_state = 0xff;
s->mpeg_enc_ctx_allocated = 0;
@@ -1468,7 +1469,7 @@ static int mpeg_decode_slice(AVCodecContext *avctx,
start_code = (start_code - 1) & 0xff;
if (start_code >= s->mb_height){
- fprintf(stderr, "slice below image\n");
+ fprintf(stderr, "slice below image (%d >= %d)\n", start_code, s->mb_height);
return -1;
}
s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
@@ -1590,7 +1591,6 @@ static int mpeg1_decode_sequence(AVCodecContext *avctx,
if (MPV_common_init(s) < 0)
return -1;
- mpeg1_init_vlc(s);
s1->mpeg_enc_ctx_allocated = 1;
}
@@ -1711,7 +1711,17 @@ static int mpeg_decode_frame(AVCodecContext *avctx,
} else {
memcpy(s->buf_ptr, buf_start, len);
s->buf_ptr += len;
-
+ if( (s2->flags&CODEC_FLAG_NOT_TRUNCATED) && (!start_code_found)
+ && s->buf_ptr+4<s->buffer+s->buffer_size){
+ start_code_found= 1;
+ code= 0x1FF;
+ s->header_state=0xFF;
+ s->buf_ptr[0]=0;
+ s->buf_ptr[1]=0;
+ s->buf_ptr[2]=1;
+ s->buf_ptr[3]=0xFF;
+ s->buf_ptr+=4;
+ }
if (start_code_found) {
/* prepare data for next start code */
input_size = s->buf_ptr - s->buffer;
--
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