avoid buf_size == 0 checks in every decoder

Originally committed as revision 3872 to svn://svn.ffmpeg.org/ffmpeg/trunk

35 files changed, 24 insertions, 148 deletions

diff --git a/libavcodec/4xm.c b/libavcodec/4xm.c
index 5cc5f575f0..6932d52ab8 100644
--- a/libavcodec/4xm.c
+++ b/libavcodec/4xm.c
@@ -605,11 +605,6 @@ static int decode_frame(AVCodecContext *avctx,
     AVFrame *p, temp;
     int i, frame_4cc, frame_size;
 
-    /* special case for last picture */
-    if (buf_size == 0) {
-        return 0;
-    }
-
     frame_4cc= get32(buf);
     if(buf_size != get32(buf+4)+8){
         av_log(f->avctx, AV_LOG_ERROR, "size missmatch %d %d\n", buf_size, get32(buf+4));
diff --git a/libavcodec/8bps.c b/libavcodec/8bps.c
index 48773a1744..3898ac5dd3 100644
--- a/libavcodec/8bps.c
+++ b/libavcodec/8bps.c
@@ -70,11 +70,6 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8
 	unsigned int planes = c->planes;
 	unsigned char *planemap = c->planemap;
   
-  
-	/* no supplementary picture */
-	if (buf_size == 0)
-		return 0;
-
 	if(c->pic.data[0])
 		avctx->release_buffer(avctx, &c->pic);
 
diff --git a/libavcodec/asv1.c b/libavcodec/asv1.c
index 95b15337bf..b8030ef3ab 100644
--- a/libavcodec/asv1.c
+++ b/libavcodec/asv1.c
@@ -409,11 +409,6 @@ static int decode_frame(AVCodecContext *avctx,
     AVFrame * const p= (AVFrame*)&a->picture;
     int mb_x, mb_y;
 
-    /* special case for last picture */
-    if (buf_size == 0) {
-        return 0;
-    }
-
     if(p->data[0])
         avctx->release_buffer(avctx, p);
 
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 8cf6500ca3..503a04e083 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -338,7 +338,10 @@ extern int motion_estimation_method;
 #define CODEC_CAP_TRUNCATED       0x0008
 /* codec can export data for HW decoding (XvMC) */
 #define CODEC_CAP_HWACCEL         0x0010
-/** codec has a non zero delay and needs to be feeded with NULL at the end to get the delayed data */
+/** 
+ * codec has a non zero delay and needs to be feeded with NULL at the end to get the delayed data.
+ * if this is not set, the codec is guranteed to never be feeded with NULL data
+ */
 #define CODEC_CAP_DELAY           0x0020
 
 //the following defines might change, so dont expect compatibility if u use them
diff --git a/libavcodec/cljr.c b/libavcodec/cljr.c
index df1f798514..c17316b3e0 100644
--- a/libavcodec/cljr.c
+++ b/libavcodec/cljr.c
@@ -43,11 +43,6 @@ static int decode_frame(AVCodecContext *avctx,
     AVFrame * const p= (AVFrame*)&a->picture;
     int x, y;
 
-    /* special case for last picture */
-    if (buf_size == 0) {
-        return 0;
-    }
-
     if(p->data[0])
         avctx->release_buffer(avctx, p);
 
diff --git a/libavcodec/dv.c b/libavcodec/dv.c
index f548bffd8b..01e1ce6842 100644
--- a/libavcodec/dv.c
+++ b/libavcodec/dv.c
@@ -888,10 +888,6 @@ static int dvvideo_decode_frame(AVCodecContext *avctx,
 {
     DVVideoContext *s = avctx->priv_data;
   
-    /* special case for last picture */
-    if(buf_size==0)
-        return 0;
-    
     s->sys = dv_frame_profile(buf);
     if (!s->sys || buf_size < s->sys->frame_size)
         return -1; /* NOTE: we only accept several full frames */
diff --git a/libavcodec/ffv1.c b/libavcodec/ffv1.c
index cc15d902b2..737e3f4114 100644
--- a/libavcodec/ffv1.c
+++ b/libavcodec/ffv1.c
@@ -952,10 +952,6 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8
 
     AVFrame *picture = data;
 
-    /* no supplementary picture */
-    if (buf_size == 0)
-        return 0;
-
     ff_init_range_decoder(c, buf, buf_size);
     ff_build_rac_states(c, 0.05*(1LL<<32), 256-8);
 
diff --git a/libavcodec/h261.c b/libavcodec/h261.c
index 8536ea9c86..aceebaa381 100644
--- a/libavcodec/h261.c
+++ b/libavcodec/h261.c
@@ -925,11 +925,6 @@ static int h261_decode_frame(AVCodecContext *avctx,
     s->flags= avctx->flags;
     s->flags2= avctx->flags2;
 
-    /* no supplementary picture */
-    if (buf_size == 0) {
-        return 0;
-    }
-    
     h->gob_start_code_skipped=0;
 
 retry:
diff --git a/libavcodec/h263dec.c b/libavcodec/h263dec.c
index da94aede5a..272780da7a 100644
--- a/libavcodec/h263dec.c
+++ b/libavcodec/h263dec.c
@@ -793,7 +793,7 @@ AVCodec mpeg4_decoder = {
     NULL,
     ff_h263_decode_end,
     ff_h263_decode_frame,
-    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
+    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
     .options = mpeg4_decoptions,
     .flush= ff_mpeg_flush,
 };
@@ -807,7 +807,7 @@ AVCodec h263_decoder = {
     NULL,
     ff_h263_decode_end,
     ff_h263_decode_frame,
-    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
+    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
     .flush= ff_mpeg_flush,
 };
 
diff --git a/libavcodec/h264.c b/libavcodec/h264.c
index 466257adaa..856b0804a4 100644
--- a/libavcodec/h264.c
+++ b/libavcodec/h264.c
@@ -6592,7 +6592,7 @@ AVCodec h264_decoder = {
     NULL,
     decode_end,
     decode_frame,
-    /*CODEC_CAP_DRAW_HORIZ_BAND |*/ CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
+    /*CODEC_CAP_DRAW_HORIZ_BAND |*/ CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
 };
 
 AVCodecParser h264_parser = {
diff --git a/libavcodec/huffyuv.c b/libavcodec/huffyuv.c
index fbc20ad5e2..ac1a8b2c85 100644
--- a/libavcodec/huffyuv.c
+++ b/libavcodec/huffyuv.c
@@ -770,10 +770,6 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8
 
     AVFrame *picture = data;
 
-    /* no supplementary picture */
-    if (buf_size == 0)
-        return 0;
-        
     s->bitstream_buffer= av_fast_realloc(s->bitstream_buffer, &s->bitstream_buffer_size, buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
 
     s->dsp.bswap_buf((uint32_t*)s->bitstream_buffer, (uint32_t*)buf, buf_size/4);
diff --git a/libavcodec/indeo3.c b/libavcodec/indeo3.c
index 24e2160e5a..099522f33c 100644
--- a/libavcodec/indeo3.c
+++ b/libavcodec/indeo3.c
@@ -1066,11 +1066,6 @@ static int indeo3_decode_frame(AVCodecContext *avctx,
     unsigned char *src, *dest;
     int y;
 
-    /* no supplementary picture */
-    if (buf_size == 0) {
-        return 0;
-    }
-
     iv_decode_frame(s, buf, buf_size);
 
     if(s->frame.data[0])
diff --git a/libavcodec/lcl.c b/libavcodec/lcl.c
index bf04154a91..e710f942a1 100644
--- a/libavcodec/lcl.c
+++ b/libavcodec/lcl.c
@@ -214,10 +214,6 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8
 #endif
     unsigned int len = buf_size;
 
-	/* no supplementary picture */
-	if (buf_size == 0)
-		return 0;
-
 	if(c->pic.data[0])
 		avctx->release_buffer(avctx, &c->pic);
 
diff --git a/libavcodec/mdec.c b/libavcodec/mdec.c
index cf3a1d347b..a71f050cde 100644
--- a/libavcodec/mdec.c
+++ b/libavcodec/mdec.c
@@ -163,11 +163,6 @@ static int decode_frame(AVCodecContext *avctx,
     AVFrame * const p= (AVFrame*)&a->picture;
     int i;
 
-    /* special case for last picture */
-    if (buf_size == 0) {
-        return 0;
-    }
-
     if(p->data[0])
         avctx->release_buffer(avctx, p);
 
diff --git a/libavcodec/mjpeg.c b/libavcodec/mjpeg.c
index 2edd90bd43..6ea01b3b84 100644
--- a/libavcodec/mjpeg.c
+++ b/libavcodec/mjpeg.c
@@ -1826,10 +1826,6 @@ static int mjpeg_decode_frame(AVCodecContext *avctx,
     int start_code;
     AVFrame *picture = data;
 
-    /* no supplementary picture */
-    if (buf_size == 0)
-        return 0;
-
     buf_ptr = buf;
     buf_end = buf + buf_size;
     while (buf_ptr < buf_end) {
@@ -2002,10 +1998,6 @@ static int mjpegb_decode_frame(AVCodecContext *avctx,
     uint32_t dqt_offs, dht_offs, sof_offs, sos_offs, second_field_offs;
     uint32_t field_size, sod_offs;
 
-    /* no supplementary picture */
-    if (buf_size == 0)
-        return 0;
-
     buf_ptr = buf;
     buf_end = buf + buf_size;
     
@@ -2115,10 +2107,6 @@ static int sp5x_decode_frame(AVCodecContext *avctx,
     uint8_t *buf_ptr, *buf_end, *recoded;
     int i = 0, j = 0;
 
-    /* no supplementary picture */
-    if (buf_size == 0)
-        return 0;
-
     if (!avctx->width || !avctx->height)
 	return -1;
 
diff --git a/libavcodec/mpeg12.c b/libavcodec/mpeg12.c
index cb24c514ad..57ce02ea6d 100644
--- a/libavcodec/mpeg12.c
+++ b/libavcodec/mpeg12.c
@@ -3100,7 +3100,7 @@ AVCodec mpeg1video_decoder = {
     NULL,
     mpeg_decode_end,
     mpeg_decode_frame,
-    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
+    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
     .flush= ff_mpeg_flush,
 };
 
@@ -3113,7 +3113,7 @@ AVCodec mpeg2video_decoder = {
     NULL,
     mpeg_decode_end,
     mpeg_decode_frame,
-    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
+    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
     .flush= ff_mpeg_flush,
 };
 
@@ -3127,7 +3127,7 @@ AVCodec mpegvideo_decoder = {
     NULL,
     mpeg_decode_end,
     mpeg_decode_frame,
-    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED,
+    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
     .flush= ff_mpeg_flush,
 };
 
@@ -3190,7 +3190,7 @@ AVCodec mpeg_xvmc_decoder = {
     NULL,
     mpeg_decode_end,
     mpeg_decode_frame,
-    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL,
+    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
     .flush= ff_mpeg_flush,
 };
 
diff --git a/libavcodec/msrle.c b/libavcodec/msrle.c
index b318faa77f..d95e3f79b5 100644
--- a/libavcodec/msrle.c
+++ b/libavcodec/msrle.c
@@ -254,10 +254,6 @@ static int msrle_decode_frame(AVCodecContext *avctx,
 {
     MsrleContext *s = (MsrleContext *)avctx->priv_data;
 
-    /* no supplementary picture */
-    if (buf_size == 0)
-        return 0;
-
     s->buf = buf;
     s->size = buf_size;
 
diff --git a/libavcodec/msvideo1.c b/libavcodec/msvideo1.c
index b88bdab5de..518df0e52d 100644
--- a/libavcodec/msvideo1.c
+++ b/libavcodec/msvideo1.c
@@ -302,10 +302,6 @@ static int msvideo1_decode_frame(AVCodecContext *avctx,
 {
     Msvideo1Context *s = (Msvideo1Context *)avctx->priv_data;
 
-    /* no supplementary picture */
-    if (buf_size == 0)
-        return 0;
-
     s->buf = buf;
     s->size = buf_size;
 
diff --git a/libavcodec/png.c b/libavcodec/png.c
index 2945d0cc54..637a229171 100644
--- a/libavcodec/png.c
+++ b/libavcodec/png.c
@@ -479,11 +479,6 @@ static int decode_frame(AVCodecContext *avctx,
     uint32_t tag, length;
     int ret, crc;
 
-    /* special case for last picture */
-    if (buf_size == 0) {
-        return 0;
-    }
-    
     s->bytestream_start=
     s->bytestream= buf;
     s->bytestream_end= buf + buf_size;
diff --git a/libavcodec/pnm.c b/libavcodec/pnm.c
index 51134ce370..3751d114aa 100644
--- a/libavcodec/pnm.c
+++ b/libavcodec/pnm.c
@@ -165,11 +165,6 @@ static int pnm_decode_frame(AVCodecContext *avctx,
     int i, n, linesize, h;
     unsigned char *ptr;
 
-    /* special case for last picture */
-    if (buf_size == 0) {
-        return 0;
-    }
-    
     s->bytestream_start=
     s->bytestream= buf;
     s->bytestream_end= buf + buf_size;
diff --git a/libavcodec/qdrw.c b/libavcodec/qdrw.c
index 0adb5f49a1..4fc9703227 100644
--- a/libavcodec/qdrw.c
+++ b/libavcodec/qdrw.c
@@ -42,11 +42,6 @@ static int decode_frame(AVCodecContext *avctx,
     int colors;
     int i;
     
-    /* special case for last picture */
-    if (buf_size == 0) {
-        return 0;
-    }
-
     if(p->data[0])
         avctx->release_buffer(avctx, p);
 
diff --git a/libavcodec/qpeg.c b/libavcodec/qpeg.c
index bb6467b331..fa945858c2 100644
--- a/libavcodec/qpeg.c
+++ b/libavcodec/qpeg.c
@@ -237,11 +237,6 @@ static int decode_frame(AVCodecContext *avctx,
     uint8_t* outdata;
     int delta;
     
-    /* special case for last picture */
-    if (buf_size == 0) {
-        return 0;
-    }
-
     if(p->data[0])
         avctx->release_buffer(avctx, p);
 
diff --git a/libavcodec/qtrle.c b/libavcodec/qtrle.c
index 1fedaccf16..41e4120dbf 100644
--- a/libavcodec/qtrle.c
+++ b/libavcodec/qtrle.c
@@ -530,10 +530,6 @@ static int qtrle_decode_frame(AVCodecContext *avctx,
 {
     QtrleContext *s = (QtrleContext *)avctx->priv_data;
 
-    /* no supplementary picture */
-    if (buf_size == 0)
-        return 0;
-
     s->buf = buf;
     s->size = buf_size;
 
diff --git a/libavcodec/rpza.c b/libavcodec/rpza.c
index 2be26346a2..317c240b9b 100644
--- a/libavcodec/rpza.c
+++ b/libavcodec/rpza.c
@@ -248,10 +248,6 @@ static int rpza_decode_frame(AVCodecContext *avctx,
 {
     RpzaContext *s = (RpzaContext *)avctx->priv_data;
 
-    /* no supplementary picture */
-    if (buf_size == 0)
-        return 0;
-
     s->buf = buf;
     s->size = buf_size;
 
diff --git a/libavcodec/rv10.c b/libavcodec/rv10.c
index 1a8ab054e0..9fb1e8df1a 100644
--- a/libavcodec/rv10.c
+++ b/libavcodec/rv10.c
@@ -763,7 +763,7 @@ AVCodec rv20_decoder = {
     NULL,
     rv10_decode_end,
     rv10_decode_frame,
-    CODEC_CAP_DR1,
+    CODEC_CAP_DR1 | CODEC_CAP_DELAY,
     .flush= ff_mpeg_flush,
 };
 
diff --git a/libavcodec/smc.c b/libavcodec/smc.c
index 47c7d93d4c..dbb5adef1d 100644
--- a/libavcodec/smc.c
+++ b/libavcodec/smc.c
@@ -448,10 +448,6 @@ static int smc_decode_frame(AVCodecContext *avctx,
 {
     SmcContext *s = (SmcContext *)avctx->priv_data;
 
-    /* no supplementary picture */
-    if (buf_size == 0)
-        return 0;
-
     s->buf = buf;
     s->size = buf_size;
 
diff --git a/libavcodec/snow.c b/libavcodec/snow.c
index 13c596d36a..3566b72fba 100644
--- a/libavcodec/snow.c
+++ b/libavcodec/snow.c
@@ -2911,11 +2911,6 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8
     int bytes_read;
     AVFrame *picture = data;
     int level, orientation, plane_index;
-    
-
-    /* no supplementary picture */
-    if (buf_size == 0)
-        return 0;
 
     ff_init_range_decoder(c, buf, buf_size);
     ff_build_rac_states(c, 0.05*(1LL<<32), 256-8);
diff --git a/libavcodec/svq1.c b/libavcodec/svq1.c
index c719a8ef22..f5c3c7774a 100644
--- a/libavcodec/svq1.c
+++ b/libavcodec/svq1.c
@@ -713,10 +713,6 @@ static int svq1_decode_frame(AVCodecContext *avctx,
   int		result, i, x, y, width, height;
   AVFrame *pict = data; 
 
-  if(buf==NULL && buf_size==0){
-      return 0;
-  }
-  
   /* initialize bit buffer */
   init_get_bits(&s->gb,buf,buf_size*8);
 
diff --git a/libavcodec/svq3.c b/libavcodec/svq3.c
index 365125165d..6c189b5e9d 100644
--- a/libavcodec/svq3.c
+++ b/libavcodec/svq3.c
@@ -1004,5 +1004,5 @@ AVCodec svq3_decoder = {
     NULL,
     decode_end,
     svq3_decode_frame,
-    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1,
+    CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_DELAY,
 };
diff --git a/libavcodec/truemotion1.c b/libavcodec/truemotion1.c
index 880ab8d2ee..0c3bb09cf1 100644
--- a/libavcodec/truemotion1.c
+++ b/libavcodec/truemotion1.c
@@ -873,10 +873,6 @@ static int truemotion1_decode_frame(AVCodecContext *avctx,
     s->buf = buf;
     s->size = buf_size;
 
-    /* no supplementary picture */
-    if (buf_size == 0)
-        return 0;
-
     if (truemotion1_decode_header(s) == -1)
         return -1;
 
diff --git a/libavcodec/tscc.c b/libavcodec/tscc.c
index 0e97ee6d92..11d8b83087 100644
--- a/libavcodec/tscc.c
+++ b/libavcodec/tscc.c
@@ -155,10 +155,6 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8
 #endif
     int len = buf_size;
 
-    /* no supplementary picture */
-    if (buf_size == 0)
-        return 0;
-
     if(c->pic.data[0])
             avctx->release_buffer(avctx, &c->pic);
 
diff --git a/libavcodec/utils.c b/libavcodec/utils.c
index c51efd110f..325883cdb8 100644
--- a/libavcodec/utils.c
+++ b/libavcodec/utils.c
@@ -587,13 +587,17 @@ int avcodec_decode_video(AVCodecContext *avctx, AVFrame *picture,
     *got_picture_ptr= 0;
     if((avctx->coded_width||avctx->coded_height) && avcodec_check_dimensions(avctx,avctx->coded_width,avctx->coded_height))
         return -1;
-    ret = avctx->codec->decode(avctx, picture, got_picture_ptr, 
-                               buf, buf_size);
+    if((avctx->codec->capabilities & CODEC_CAP_DELAY) || buf_size){
+        ret = avctx->codec->decode(avctx, picture, got_picture_ptr, 
+                                buf, buf_size);
 
-    emms_c(); //needed to avoid a emms_c() call before every return;
+        emms_c(); //needed to avoid a emms_c() call before every return;
     
-    if (*got_picture_ptr)                           
-        avctx->frame_number++;
+        if (*got_picture_ptr)                           
+            avctx->frame_number++;
+    }else
+        ret= 0;
+
     return ret;
 }
 
diff --git a/libavcodec/vc9.c b/libavcodec/vc9.c
index 8f469d074c..df1f695ebd 100644
--- a/libavcodec/vc9.c
+++ b/libavcodec/vc9.c
@@ -1705,7 +1705,7 @@ AVCodec vc9_decoder = {
     NULL,
     vc9_decode_end,
     vc9_decode_frame,
-    0,
+    CODEC_CAP_DELAY,
     NULL
 };
 
@@ -1718,6 +1718,6 @@ AVCodec wmv3_decoder = {
     NULL,
     vc9_decode_end,
     vc9_decode_frame,
-    0,
+    CODEC_CAP_DELAY,
     NULL
 };
diff --git a/libavcodec/vcr1.c b/libavcodec/vcr1.c
index 9a706af315..5a55d9f7fa 100644
--- a/libavcodec/vcr1.c
+++ b/libavcodec/vcr1.c
@@ -45,11 +45,6 @@ static int decode_frame(AVCodecContext *avctx,
     uint8_t *bytestream= buf;
     int i, x, y;
 
-    /* special case for last picture */
-    if (buf_size == 0) {
-        return 0;
-    }
-
     if(p->data[0])
         avctx->release_buffer(avctx, p);
 
diff --git a/libavcodec/xl.c b/libavcodec/xl.c
index 0f496017d9..2ba48eb278 100644
--- a/libavcodec/xl.c
+++ b/libavcodec/xl.c
@@ -48,12 +48,6 @@ static int decode_frame(AVCodecContext *avctx,
     int stride;
     uint32_t val;
     int y0, y1, y2, y3, c0, c1;
-        
-    
-    /* special case for last picture */
-    if (buf_size == 0) {
-        return 0;
-    }
 
     if(p->data[0])
         avctx->release_buffer(avctx, p);