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/*
* HEVC common code
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <string.h>
#include "config.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/mem.h"
#include "hevc.h"
/* FIXME: This is adapted from ff_h264_decode_nal, avoiding duplication
* between these functions would be nice. */
int ff_hevc_extract_rbsp(const uint8_t *src, int length,
HEVCNAL *nal)
{
int i, si, di;
uint8_t *dst;
nal->skipped_bytes = 0;
#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 /* HAVE_FAST_64BIT */
#else
for (i = 0; i + 1 < length; i += 2) {
if (src[i])
continue;
if (i > 0 && src[i - 1] == 0)
i--;
STARTCODE_TEST;
}
#endif /* HAVE_FAST_UNALIGNED */
if (i >= length - 1) { // no escaped 0
nal->data =
nal->raw_data = src;
nal->size =
nal->raw_size = length;
return length;
}
av_fast_malloc(&nal->rbsp_buffer, &nal->rbsp_buffer_size,
length + AV_INPUT_BUFFER_PADDING_SIZE);
if (!nal->rbsp_buffer)
return AVERROR(ENOMEM);
dst = nal->rbsp_buffer;
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;
if (nal->skipped_bytes_pos) {
nal->skipped_bytes++;
if (nal->skipped_bytes_pos_size < nal->skipped_bytes) {
nal->skipped_bytes_pos_size *= 2;
av_assert0(nal->skipped_bytes_pos_size >= nal->skipped_bytes);
av_reallocp_array(&nal->skipped_bytes_pos,
nal->skipped_bytes_pos_size,
sizeof(*nal->skipped_bytes_pos));
if (!nal->skipped_bytes_pos) {
nal->skipped_bytes_pos_size = 0;
return AVERROR(ENOMEM);
}
}
if (nal->skipped_bytes_pos)
nal->skipped_bytes_pos[nal->skipped_bytes-1] = di - 1;
}
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);
nal->data = dst;
nal->size = di;
nal->raw_data = src;
nal->raw_size = si;
return si;
}
static const char *nal_unit_name(int nal_type)
{
switch(nal_type) {
case NAL_TRAIL_N : return "TRAIL_N";
case NAL_TRAIL_R : return "TRAIL_R";
case NAL_TSA_N : return "TSA_N";
case NAL_TSA_R : return "TSA_R";
case NAL_STSA_N : return "STSA_N";
case NAL_STSA_R : return "STSA_R";
case NAL_RADL_N : return "RADL_N";
case NAL_RADL_R : return "RADL_R";
case NAL_RASL_N : return "RASL_N";
case NAL_RASL_R : return "RASL_R";
case NAL_BLA_W_LP : return "BLA_W_LP";
case NAL_BLA_W_RADL : return "BLA_W_RADL";
case NAL_BLA_N_LP : return "BLA_N_LP";
case NAL_IDR_W_RADL : return "IDR_W_RADL";
case NAL_IDR_N_LP : return "IDR_N_LP";
case NAL_CRA_NUT : return "CRA_NUT";
case NAL_VPS : return "VPS";
case NAL_SPS : return "SPS";
case NAL_PPS : return "PPS";
case NAL_AUD : return "AUD";
case NAL_EOS_NUT : return "EOS_NUT";
case NAL_EOB_NUT : return "EOB_NUT";
case NAL_FD_NUT : return "FD_NUT";
case NAL_SEI_PREFIX : return "SEI_PREFIX";
case NAL_SEI_SUFFIX : return "SEI_SUFFIX";
default : return "?";
}
}
/**
* @return AVERROR_INVALIDDATA if the packet is not a valid NAL unit,
* 0 if the unit should be skipped, 1 otherwise
*/
static int hls_nal_unit(HEVCNAL *nal, AVCodecContext *avctx)
{
GetBitContext *gb = &nal->gb;
int nuh_layer_id;
if (get_bits1(gb) != 0)
return AVERROR_INVALIDDATA;
nal->type = get_bits(gb, 6);
nuh_layer_id = get_bits(gb, 6);
nal->temporal_id = get_bits(gb, 3) - 1;
if (nal->temporal_id < 0)
return AVERROR_INVALIDDATA;
av_log(avctx, AV_LOG_DEBUG,
"nal_unit_type: %d(%s), nuh_layer_id: %d, temporal_id: %d\n",
nal->type, nal_unit_name(nal->type), nuh_layer_id, nal->temporal_id);
return nuh_layer_id == 0;
}
int ff_hevc_split_packet(HEVCPacket *pkt, const uint8_t *buf, int length,
AVCodecContext *avctx, int is_nalff, int nal_length_size)
{
int consumed, ret = 0;
pkt->nb_nals = 0;
while (length >= 4) {
HEVCNAL *nal;
int extract_length = 0;
if (is_nalff) {
int i;
for (i = 0; i < nal_length_size; i++)
extract_length = (extract_length << 8) | buf[i];
buf += nal_length_size;
length -= nal_length_size;
if (extract_length > length) {
av_log(avctx, AV_LOG_ERROR, "Invalid NAL unit size.\n");
return AVERROR_INVALIDDATA;
}
} else {
/* search start code */
while (buf[0] != 0 || buf[1] != 0 || buf[2] != 1) {
++buf;
--length;
if (length < 4) {
if (pkt->nb_nals > 0) {
// No more start codes: we discarded some irrelevant
// bytes at the end of the packet.
return 0;
} else {
av_log(avctx, AV_LOG_ERROR, "No start code is found.\n");
return AVERROR_INVALIDDATA;
}
}
}
buf += 3;
length -= 3;
extract_length = length;
}
if (pkt->nals_allocated < pkt->nb_nals + 1) {
int new_size = pkt->nals_allocated + 1;
void *tmp = av_realloc_array(pkt->nals, new_size, sizeof(*pkt->nals));
if (!tmp)
return AVERROR(ENOMEM);
pkt->nals = tmp;
memset(pkt->nals + pkt->nals_allocated, 0,
(new_size - pkt->nals_allocated) * sizeof(*pkt->nals));
nal = &pkt->nals[pkt->nb_nals];
nal->skipped_bytes_pos_size = 1024; // initial buffer size
nal->skipped_bytes_pos = av_malloc_array(nal->skipped_bytes_pos_size, sizeof(*nal->skipped_bytes_pos));
if (!nal->skipped_bytes_pos)
return AVERROR(ENOMEM);
pkt->nals_allocated = new_size;
}
nal = &pkt->nals[pkt->nb_nals];
consumed = ff_hevc_extract_rbsp(buf, extract_length, nal);
if (consumed < 0)
return consumed;
pkt->nb_nals++;
ret = init_get_bits8(&nal->gb, nal->data, nal->size);
if (ret < 0)
return ret;
ret = hls_nal_unit(nal, avctx);
if (ret <= 0) {
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR, "Invalid NAL unit %d, skipping.\n",
nal->type);
}
pkt->nb_nals--;
}
buf += consumed;
length -= consumed;
}
return 0;
}
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