[SCM] libav/experimental: - Bug fix on inter MCBPC table for inter+q. - H.263/H.263+ decoder now knows GOB start codes. - H.263/H.263+ decoder now returns the size of the stream on the first call. - Added show_bits() functions to see the buffer without loosing the bits. - TODO: H.263v1 UMV parsing is buggy.
siretart at users.alioth.debian.org
siretart at users.alioth.debian.org
Sun Jun 30 15:30:26 UTC 2013
The following commit has been merged in the experimental branch:
commit 4949028f85dec72a5caf322757a6e6fd6ef711d3
Author: Juanjo <pulento at users.sourceforge.net>
Date: Sat Nov 3 00:49:53 2001 +0000
- Bug fix on inter MCBPC table for inter+q.
- H.263/H.263+ decoder now knows GOB start codes.
- H.263/H.263+ decoder now returns the size of the stream on the first call.
- Added show_bits() functions to see the buffer without loosing the bits.
- TODO: H.263v1 UMV parsing is buggy.
Originally committed as revision 204 to svn://svn.ffmpeg.org/ffmpeg/trunk
diff --git a/libavcodec/common.c b/libavcodec/common.c
index 2f7cafc..aa45c35 100644
--- a/libavcodec/common.c
+++ b/libavcodec/common.c
@@ -250,6 +250,52 @@ void align_get_bits(GetBitContext *s)
get_bits(s, n);
}
}
+/* This function is identical to get_bits_long(), the */
+/* only diference is that it doesn't touch the buffer */
+/* it is usefull to see the buffer. */
+
+unsigned int show_bits_long(GetBitContext *s, int n)
+{
+ unsigned int val;
+ int bit_cnt;
+ unsigned int bit_buf;
+ UINT8 *buf_ptr;
+
+ bit_buf = s->bit_buf;
+ bit_cnt = s->bit_cnt - n;
+
+ val = bit_buf >> (32 - n);
+ buf_ptr = s->buf_ptr;
+ buf_ptr += 4;
+
+ /* handle common case: we can read everything */
+ if (buf_ptr <= s->buf_end) {
+#ifdef ARCH_X86
+ bit_buf = bswap_32(*((unsigned long*)(&buf_ptr[-4])));
+#else
+ bit_buf = (buf_ptr[-4] << 24) |
+ (buf_ptr[-3] << 16) |
+ (buf_ptr[-2] << 8) |
+ (buf_ptr[-1]);
+#endif
+ } else {
+ buf_ptr -= 4;
+ bit_buf = 0;
+ if (buf_ptr < s->buf_end)
+ bit_buf |= *buf_ptr++ << 24;
+ if (buf_ptr < s->buf_end)
+ bit_buf |= *buf_ptr++ << 16;
+ if (buf_ptr < s->buf_end)
+ bit_buf |= *buf_ptr++ << 8;
+ if (buf_ptr < s->buf_end)
+ bit_buf |= *buf_ptr++;
+ }
+ val |= bit_buf >> (32 + bit_cnt);
+ bit_buf <<= - bit_cnt;
+ bit_cnt += 32;
+
+ return val;
+}
/* VLC decoding */
diff --git a/libavcodec/common.h b/libavcodec/common.h
index aafcf5f..2b1deba 100644
--- a/libavcodec/common.h
+++ b/libavcodec/common.h
@@ -196,6 +196,7 @@ void init_get_bits(GetBitContext *s,
UINT8 *buffer, int buffer_size);
unsigned int get_bits_long(GetBitContext *s, int n);
+unsigned int show_bits_long(GetBitContext *s, int n);
static inline unsigned int get_bits(GetBitContext *s, int n){
if(s->bit_cnt>=n){
@@ -225,6 +226,19 @@ static inline unsigned int get_bits1(GetBitContext *s){
return get_bits_long(s,1);
}
+/* This function is identical to get_bits(), the only */
+/* diference is that it doesn't touch the buffer */
+/* it is usefull to see the buffer. */
+static inline unsigned int show_bits(GetBitContext *s, int n)
+{
+ if(s->bit_cnt>=n) {
+ /* most common case here */
+ unsigned int val = s->bit_buf >> (32 - n);
+ return val;
+ }
+ return show_bits_long(s,n);
+}
+
static inline void skip_bits(GetBitContext *s, int n){
if(s->bit_cnt>=n){
/* most common case here */
diff --git a/libavcodec/h263.c b/libavcodec/h263.c
index bef779f..138276c 100644
--- a/libavcodec/h263.c
+++ b/libavcodec/h263.c
@@ -38,7 +38,6 @@ static int h263_decode_block(MpegEncContext * s, DCTELEM * block,
static int mpeg4_decode_block(MpegEncContext * s, DCTELEM * block,
int n, int coded);
-
int h263_get_picture_format(int width, int height)
{
int format;
@@ -777,9 +776,35 @@ int h263_decode_mb(MpegEncContext *s,
DCTELEM block[6][64])
{
int cbpc, cbpy, i, cbp, pred_x, pred_y, mx, my, dquant;
+ unsigned int val;
INT16 *mot_val;
static INT8 quant_tab[4] = { -1, -2, 1, 2 };
-
+
+ /* Check for GOB Start Code */
+ val = show_bits(&s->gb, 16);
+
+ if (val == 0) {
+ /* We have a GBSC probably with GSTUFF */
+#ifdef DEBUG
+ unsigned int gn, gfid;
+#endif
+ //skip_bits(&s->gb, 16); /* Drop the zeros */
+ while (get_bits1(&s->gb) == 0); /* Seek the '1' bit */
+#ifdef DEBUG
+ fprintf(stderr,"\nGOB Start Code at MB %d\n",
+ (s->mb_y * s->mb_width) + s->mb_x);
+ gn = get_bits(&s->gb, 5); /* GN */
+ gfid = get_bits(&s->gb, 2); /* GFID */
+#else
+ skip_bits(&s->gb, 5); /* GN */
+ skip_bits(&s->gb, 2); /* GFID */
+#endif
+ s->qscale = get_bits(&s->gb, 5); /* GQUANT */
+#ifdef DEBUG
+ fprintf(stderr, "\nGN: %u GFID: %u Quant: %u\n", gn, gfid, s->qscale);
+#endif
+ }
+
if (s->pict_type == P_TYPE) {
if (get_bits1(&s->gb)) {
/* skip mb */
@@ -794,8 +819,10 @@ int h263_decode_mb(MpegEncContext *s,
return 0;
}
cbpc = get_vlc(&s->gb, &inter_MCBPC_vlc);
+ //fprintf(stderr, "\tCBPC: %d", cbpc);
if (cbpc < 0)
return -1;
+
dquant = cbpc & 8;
s->mb_intra = ((cbpc & 4) != 0);
} else {
@@ -866,7 +893,7 @@ int h263_decode_mb(MpegEncContext *s,
}
} else {
s->ac_pred = 0;
- if (s->h263_pred) {
+ if (s->h263_pred) {
s->ac_pred = get_bits1(&s->gb);
}
cbpy = get_vlc(&s->gb, &cbpy_vlc);
@@ -1261,6 +1288,7 @@ int h263_decode_picture_header(MpegEncContext *s)
s->f_code = 1;
s->width = width;
s->height = height;
+
return 0;
}
@@ -1462,3 +1490,4 @@ int intel_h263_decode_picture_header(MpegEncContext *s)
s->f_code = 1;
return 0;
}
+
diff --git a/libavcodec/h263data.h b/libavcodec/h263data.h
index 4fd9d36..6965525 100644
--- a/libavcodec/h263data.h
+++ b/libavcodec/h263data.h
@@ -4,6 +4,23 @@ static const UINT8 intra_MCBPC_code[8] = { 1, 1, 2, 3, 1, 1, 2, 3 };
static const UINT8 intra_MCBPC_bits[8] = { 1, 3, 3, 3, 4, 6, 6, 6 };
/* inter MCBPC, mb_type = (inter), (intra), (interq), (intraq), (inter4v) */
+/* Changed the tables for interq, following the standard ** Juanjo ** */
+static const UINT8 inter_MCBPC_code[20] = {
+ 1, 3, 2, 5,
+ 3, 4, 3, 3,
+ 3, 7, 6, 5,
+ 4, 4, 3, 2,
+ 2, 5, 4, 5,
+};
+static const UINT8 inter_MCBPC_bits[20] = {
+ 1, 4, 4, 6,
+ 5, 8, 8, 7,
+ 3, 7, 7, 9,
+ 6, 9, 9, 9,
+ 3, 7, 7, 8,
+};
+
+/* This is the old table
static const UINT8 inter_MCBPC_code[20] = {
1, 3, 2, 5,
3, 4, 3, 3,
@@ -17,7 +34,7 @@ static const UINT8 inter_MCBPC_bits[20] = {
12, 12, 12, 12,
6, 9, 9, 9,
3, 7, 7, 8,
-};
+};*/
static const UINT8 cbpy_tab[16][2] =
{
diff --git a/libavcodec/h263dec.c b/libavcodec/h263dec.c
index 7f2a6dd..99d7277 100644
--- a/libavcodec/h263dec.c
+++ b/libavcodec/h263dec.c
@@ -56,8 +56,9 @@ static int h263_decode_init(AVCodecContext *avctx)
}
/* for h263, we allocate the images after having read the header */
- if (MPV_common_init(s) < 0)
- return -1;
+ if (avctx->codec->id != CODEC_ID_H263)
+ if (MPV_common_init(s) < 0)
+ return -1;
/* XXX: suppress this matrix init, only needed because using mpeg1
dequantize in mmx case */
@@ -92,7 +93,7 @@ static int h263_decode_frame(AVCodecContext *avctx,
printf("*****frame %d size=%d\n", avctx->frame_number, buf_size);
printf("bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
#endif
-
+
/* no supplementary picture */
if (buf_size == 0) {
*data_size = 0;
@@ -110,6 +111,16 @@ static int h263_decode_frame(AVCodecContext *avctx,
ret = intel_h263_decode_picture_header(s);
} else {
ret = h263_decode_picture_header(s);
+ /* After H263 header decode we have the height, width, */
+ /* and other parameters. So then we could init the picture */
+ if (s->width != avctx->width || s->height != avctx->height) {
+ avctx->width = s->width;
+ avctx->height = s->height;
+ /* FIXME: By the way H263 decoder is evolving it should have */
+ /* an H263EncContext */
+ if (MPV_common_init(s) < 0)
+ return -1;
+ }
}
if (ret < 0)
return -1;
@@ -126,6 +137,7 @@ static int h263_decode_frame(AVCodecContext *avctx,
#ifdef DEBUG
printf("**mb x=%d y=%d\n", s->mb_x, s->mb_y);
#endif
+ //fprintf(stderr,"\nFrame: %d\tMB: %d",avctx->frame_number, (s->mb_y * s->mb_width) + s->mb_x);
/* DCT & quantize */
if (s->h263_msmpeg4) {
msmpeg4_dc_scale(s);
--
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