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h264_parser: switch to h2645_parse for NAL unescaping

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Remove now unused ff_h264_decode_nal().
pull/215/head
Anton Khirnov 9 years ago
parent f3ed484953
commit 8d0cc8ca97
4 changed files with 28 additions and 128 deletions
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  1. 2
      libavcodec/Makefile
  2. 106
      libavcodec/h264.c
  3. 11
      libavcodec/h264.h
  4. 37
      libavcodec/h264_parser.c

2
libavcodec/Makefile
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@ -728,7 +728,7 @@ OBJS-$(CONFIG_FLAC_PARSER) += flac_parser.o flacdata.o flac.o
OBJS-$(CONFIG_GSM_PARSER) += gsm_parser.o
OBJS-$(CONFIG_H261_PARSER) += h261_parser.o
OBJS-$(CONFIG_H263_PARSER) += h263_parser.o
OBJS-$(CONFIG_H264_PARSER) += h264_parser.o h264_parse.o
OBJS-$(CONFIG_H264_PARSER) += h264_parser.o h264_parse.o h2645_parse.o
OBJS-$(CONFIG_HEVC_PARSER) += hevc_parser.o h2645_parse.o hevc_ps.o hevc_data.o
OBJS-$(CONFIG_MJPEG_PARSER) += mjpeg_parser.o
OBJS-$(CONFIG_MLP_PARSER) += mlp_parser.o mlp.o

106
libavcodec/h264.c
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@ -116,112 +116,6 @@ void ff_h264_draw_horiz_band(const H264Context *h, H264SliceContext *sl,
}
}
const uint8_t *ff_h264_decode_nal(H264Context *h, H264SliceContext *sl,
const uint8_t *src,
int *dst_length, int *consumed, int length)
{
int i, si, di;
uint8_t *dst;
// src[0]&0x80; // forbidden bit
h->nal_ref_idc = src[0] >> 5;
h->nal_unit_type = src[0] & 0x1F;
src++;
length--;
#define STARTCODE_TEST \
if (i + 2 < length && src[i + 1] == 0 && src[i + 2] <= 3) { \
if (src[i + 2] != 3) { \
/* startcode, so we must be past the end */ \
length = i; \
} \
break; \
}
#if HAVE_FAST_UNALIGNED
#define FIND_FIRST_ZERO \
if (i > 0 && !src[i]) \
i--; \
while (src[i]) \
i++
#if HAVE_FAST_64BIT
for (i = 0; i + 1 < length; i += 9) {
if (!((~AV_RN64A(src + i) &
(AV_RN64A(src + i) - 0x0100010001000101ULL)) &
0x8000800080008080ULL))
continue;
FIND_FIRST_ZERO;
STARTCODE_TEST;
i -= 7;
}
#else
for (i = 0; i + 1 < length; i += 5) {
if (!((~AV_RN32A(src + i) &
(AV_RN32A(src + i) - 0x01000101U)) &
0x80008080U))
continue;
FIND_FIRST_ZERO;
STARTCODE_TEST;
i -= 3;
}
#endif
#else
for (i = 0; i + 1 < length; i += 2) {
if (src[i])
continue;
if (i > 0 && src[i - 1] == 0)
i--;
STARTCODE_TEST;
}
#endif
if (i >= length - 1) { // no escaped 0
*dst_length = length;
*consumed = length + 1; // +1 for the header
return src;
}
av_fast_malloc(&sl->rbsp_buffer, &sl->rbsp_buffer_size,
length + AV_INPUT_BUFFER_PADDING_SIZE);
dst = sl->rbsp_buffer;
if (!dst)
return NULL;
memcpy(dst, src, i);
si = di = i;
while (si + 2 < length) {
// remove escapes (very rare 1:2^22)
if (src[si + 2] > 3) {
dst[di++] = src[si++];
dst[di++] = src[si++];
} else if (src[si] == 0 && src[si + 1] == 0) {
if (src[si + 2] == 3) { // escape
dst[di++] = 0;
dst[di++] = 0;
si += 3;
continue;
} else // next start code
goto nsc;
}
dst[di++] = src[si++];
}
while (si < length)
dst[di++] = src[si++];
nsc:
memset(dst + di, 0, AV_INPUT_BUFFER_PADDING_SIZE);
*dst_length = di;
*consumed = si + 1; // +1 for the header
/* FIXME store exact number of bits in the getbitcontext
* (it is needed for decoding) */
return dst;
}
void ff_h264_free_tables(H264Context *h)
{
int i;

11
libavcodec/h264.h
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@ -768,17 +768,6 @@ int ff_h264_get_profile(SPS *sps);
*/
int ff_h264_decode_picture_parameter_set(H264Context *h, int bit_length);
/**
* Decode a network abstraction layer unit.
* @param consumed is the number of bytes used as input
* @param length is the length of the array
* @param dst_length is the number of decoded bytes FIXME here
* or a decode rbsp tailing?
* @return decoded bytes, might be src+1 if no escapes
*/
const uint8_t *ff_h264_decode_nal(H264Context *h, H264SliceContext *sl, const uint8_t *src,
int *dst_length, int *consumed, int length);
/**
* Free any data that may have been allocated in the H264 context
* like SPS, PPS etc.

37
libavcodec/h264_parser.c
Unescape View File

@ -195,11 +195,14 @@ static inline int parse_nal_units(AVCodecParserContext *s,
H264Context *h = &p->h;
H264SliceContext *sl = &h->slice_ctx[0];
const uint8_t *buf_end = buf + buf_size;
H2645NAL nal = { NULL };
unsigned int pps_id;
unsigned int slice_type;
int state = -1, got_reset = 0;
const uint8_t *ptr;
int field_poc[2];
int ret;
/* set some sane default values */
s->pict_type = AV_PICTURE_TYPE_I;
@ -213,7 +216,7 @@ static inline int parse_nal_units(AVCodecParserContext *s,
return 0;
for (;;) {
int src_length, dst_length, consumed;
int src_length, consumed;
buf = avpriv_find_start_code(buf, buf_end, &state);
if (buf >= buf_end)
break;
@ -235,11 +238,22 @@ static inline int parse_nal_units(AVCodecParserContext *s,
}
break;
}
ptr = ff_h264_decode_nal(h, sl, buf, &dst_length, &consumed, src_length);
if (!ptr || dst_length < 0)
consumed = ff_h2645_extract_rbsp(buf, src_length, &nal);
if (consumed < 0)
break;
init_get_bits(&h->gb, ptr, 8 * dst_length);
ret = init_get_bits(&nal.gb, nal.data, nal.size * 8);
if (ret < 0)
goto fail;
get_bits1(&nal.gb);
nal.ref_idc = get_bits(&nal.gb, 2);
nal.type = get_bits(&nal.gb, 5);
h->gb = nal.gb;
h->nal_ref_idc = nal.ref_idc;
h->nal_unit_type = nal.type;
switch (h->nal_unit_type) {
case NAL_SPS:
ff_h264_decode_seq_parameter_set(h);
@ -259,7 +273,7 @@ static inline int parse_nal_units(AVCodecParserContext *s,
h->prev_poc_lsb = 0;
/* fall through */
case NAL_SLICE:
init_get_bits(&sl->gb, ptr, 8 * dst_length);
sl->gb = nal.gb;
get_ue_golomb(&sl->gb); // skip first_mb_in_slice
slice_type = get_ue_golomb_31(&sl->gb);
s->pict_type = ff_h264_golomb_to_pict_type[slice_type % 5];
@ -271,18 +285,18 @@ static inline int parse_nal_units(AVCodecParserContext *s,
if (pps_id >= MAX_PPS_COUNT) {
av_log(h->avctx, AV_LOG_ERROR,
"pps_id %u out of range\n", pps_id);
return -1;
goto fail;
}
if (!h->pps_buffers[pps_id]) {
av_log(h->avctx, AV_LOG_ERROR,
"non-existing PPS %u referenced\n", pps_id);
return -1;
goto fail;
}
h->pps = *h->pps_buffers[pps_id];
if (!h->sps_buffers[h->pps.sps_id]) {
av_log(h->avctx, AV_LOG_ERROR,
"non-existing SPS %u referenced\n", h->pps.sps_id);
return -1;
goto fail;
}
h->sps = *h->sps_buffers[h->pps.sps_id];
h->frame_num = get_bits(&sl->gb, h->sps.log2_max_frame_num);
@ -360,7 +374,7 @@ static inline int parse_nal_units(AVCodecParserContext *s,
if (h->nal_ref_idc && h->nal_unit_type != NAL_IDR_SLICE) {
got_reset = scan_mmco_reset(s);
if (got_reset < 0)
return got_reset;
goto fail;
}
/* Set up the prev_ values for decoding POC of the next picture. */
@ -438,12 +452,15 @@ static inline int parse_nal_units(AVCodecParserContext *s,
s->field_order = AV_FIELD_UNKNOWN;
}
av_freep(&nal.rbsp_buffer);
return 0; /* no need to evaluate the rest */
}
buf += consumed;
}
/* didn't find a picture! */
av_log(h->avctx, AV_LOG_ERROR, "missing picture in access unit\n");
fail:
av_freep(&nal.rbsp_buffer);
return -1;
}

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