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Merge commit '83b2b34d06e74cc8775ba3d833f9782505e17539'

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* commit '83b2b34d06e74cc8775ba3d833f9782505e17539':
  h2645_parse: use the bytestream2 API for packet splitting

Merged-by: James Almer <jamrial@gmail.com>
This commit is contained in:
James Almer 2017-10-20 19:04:53 -03:00
commit 07cf202614
1 changed files with 49 additions and 36 deletions
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85
libavcodec/h2645_parse.c
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@ -26,6 +26,7 @@
#include "libavutil/intreadwrite.h" #include "libavutil/intreadwrite.h"
#include "libavutil/mem.h" #include "libavutil/mem.h"
#include "bytestream.h"
#include "hevc.h" #include "hevc.h"
#include "h2645_parse.h" #include "h2645_parse.h"
@ -247,60 +248,74 @@ static int h264_parse_nal_header(H2645NAL *nal, void *logctx)
return 1; return 1;
} }
static int find_next_start_code(const uint8_t *buf, const uint8_t *next_avc)
{
int i = 0;
if (buf + 3 >= next_avc)
return next_avc - buf;
while (buf + i + 3 < next_avc) {
if (buf[i] == 0 && buf[i + 1] == 0 && buf[i + 2] == 1)
break;
i++;
}
return i + 3;
}
int ff_h2645_packet_split(H2645Packet *pkt, const uint8_t *buf, int length, int ff_h2645_packet_split(H2645Packet *pkt, const uint8_t *buf, int length,
void *logctx, int is_nalff, int nal_length_size, void *logctx, int is_nalff, int nal_length_size,
enum AVCodecID codec_id, int small_padding) enum AVCodecID codec_id, int small_padding)
{ {
GetByteContext bc;
int consumed, ret = 0; int consumed, ret = 0;
const uint8_t *next_avc = is_nalff ? buf : buf + length; int next_avc = is_nalff ? 0 : length;
bytestream2_init(&bc, buf, length);
pkt->nb_nals = 0; pkt->nb_nals = 0;
while (length >= 4) { while (bytestream2_get_bytes_left(&bc) >= 4) {
H2645NAL *nal; H2645NAL *nal;
int extract_length = 0; int extract_length = 0;
int skip_trailing_zeros = 1; int skip_trailing_zeros = 1;
if (buf == next_avc) { if (bytestream2_tell(&bc) == next_avc) {
int i = 0; int i = 0;
extract_length = get_nalsize(nal_length_size, extract_length = get_nalsize(nal_length_size,
buf, length, &i, logctx); bc.buffer, bytestream2_get_bytes_left(&bc), &i, logctx);
if (extract_length < 0) if (extract_length < 0)
return extract_length; return extract_length;
buf += nal_length_size; bytestream2_skip(&bc, nal_length_size);
length -= nal_length_size;
next_avc = buf + extract_length; next_avc = bytestream2_tell(&bc) + extract_length;
} else { } else {
if (buf > next_avc) int buf_index;
if (bytestream2_tell(&bc) > next_avc)
av_log(logctx, AV_LOG_WARNING, "Exceeded next NALFF position, re-syncing.\n"); av_log(logctx, AV_LOG_WARNING, "Exceeded next NALFF position, re-syncing.\n");
/* search start code */ /* search start code */
while (buf[0] != 0 || buf[1] != 0 || buf[2] != 1) { buf_index = find_next_start_code(bc.buffer, buf + next_avc);
++buf;
--length; bytestream2_skip(&bc, buf_index);
if (length < 4) {
if (pkt->nb_nals > 0) { if (!bytestream2_get_bytes_left(&bc)) {
// No more start codes: we discarded some irrelevant if (pkt->nb_nals > 0) {
// bytes at the end of the packet. // No more start codes: we discarded some irrelevant
return 0; // bytes at the end of the packet.
} else { return 0;
av_log(logctx, AV_LOG_ERROR, "No start code is found.\n"); } else {
return AVERROR_INVALIDDATA; av_log(logctx, AV_LOG_ERROR, "No start code is found.\n");
} return AVERROR_INVALIDDATA;
} else if (buf >= (next_avc - 3)) }
break;
} }
buf += 3; extract_length = FFMIN(bytestream2_get_bytes_left(&bc), next_avc - bytestream2_tell(&bc));
length -= 3;
extract_length = FFMIN(length, next_avc - buf);
if (buf >= next_avc) { if (bytestream2_tell(&bc) >= next_avc) {
/* skip to the start of the next NAL */ /* skip to the start of the next NAL */
int offset = next_avc - buf; bytestream2_skip(&bc, next_avc - bytestream2_tell(&bc));
buf += offset;
length -= offset;
continue; continue;
} }
} }
@ -326,7 +341,7 @@ int ff_h2645_packet_split(H2645Packet *pkt, const uint8_t *buf, int length,
} }
nal = &pkt->nals[pkt->nb_nals]; nal = &pkt->nals[pkt->nb_nals];
consumed = ff_h2645_extract_rbsp(buf, extract_length, nal, small_padding); consumed = ff_h2645_extract_rbsp(bc.buffer, extract_length, nal, small_padding);
if (consumed < 0) if (consumed < 0)
return consumed; return consumed;
@ -337,10 +352,11 @@ int ff_h2645_packet_split(H2645Packet *pkt, const uint8_t *buf, int length,
pkt->nb_nals++; pkt->nb_nals++;
bytestream2_skip(&bc, consumed);
/* see commit 3566042a0 */ /* see commit 3566042a0 */
if (consumed < length - 3 && if (bytestream2_get_bytes_left(&bc) >= 4 &&
buf[consumed] == 0x00 && buf[consumed + 1] == 0x00 && bytestream2_peek_be32(&bc) == 0x000001E0)
buf[consumed + 2] == 0x01 && buf[consumed + 3] == 0xE0)
skip_trailing_zeros = 0; skip_trailing_zeros = 0;
nal->size_bits = get_bit_length(nal, skip_trailing_zeros); nal->size_bits = get_bit_length(nal, skip_trailing_zeros);
@ -360,9 +376,6 @@ int ff_h2645_packet_split(H2645Packet *pkt, const uint8_t *buf, int length,
} }
pkt->nb_nals--; pkt->nb_nals--;
} }
buf += consumed;
length -= consumed;
} }
return 0; return 0;