| /* |
| * H.264/HEVC common parsing 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/intmath.h" |
| #include "libavutil/intreadwrite.h" |
| #include "libavutil/mem.h" |
| |
| #include "hevc.h" |
| #include "h2645_parse.h" |
| |
| int ff_h2645_extract_rbsp(const uint8_t *src, int length, |
| H2645NAL *nal, int small_padding) |
| { |
| int i, si, di; |
| uint8_t *dst; |
| int64_t padding = small_padding ? 0 : MAX_MBPAIR_SIZE; |
| |
| nal->skipped_bytes = 0; |
| #define STARTCODE_TEST \ |
| if (i + 2 < length && src[i + 1] == 0 && src[i + 2] <= 3) { \ |
| if (src[i + 2] != 3 && src[i + 2] != 0) { \ |
| /* 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 && small_padding) { // no escaped 0 |
| nal->data = |
| nal->raw_data = src; |
| nal->size = |
| nal->raw_size = length; |
| return length; |
| } else if (i > length) |
| i = length; |
| |
| av_fast_padded_malloc(&nal->rbsp_buffer, &nal->rbsp_buffer_size, |
| length + padding); |
| 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 && src[si + 2] != 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 HEVC_NAL_TRAIL_N : return "TRAIL_N"; |
| case HEVC_NAL_TRAIL_R : return "TRAIL_R"; |
| case HEVC_NAL_TSA_N : return "TSA_N"; |
| case HEVC_NAL_TSA_R : return "TSA_R"; |
| case HEVC_NAL_STSA_N : return "STSA_N"; |
| case HEVC_NAL_STSA_R : return "STSA_R"; |
| case HEVC_NAL_RADL_N : return "RADL_N"; |
| case HEVC_NAL_RADL_R : return "RADL_R"; |
| case HEVC_NAL_RASL_N : return "RASL_N"; |
| case HEVC_NAL_RASL_R : return "RASL_R"; |
| case HEVC_NAL_BLA_W_LP : return "BLA_W_LP"; |
| case HEVC_NAL_BLA_W_RADL : return "BLA_W_RADL"; |
| case HEVC_NAL_BLA_N_LP : return "BLA_N_LP"; |
| case HEVC_NAL_IDR_W_RADL : return "IDR_W_RADL"; |
| case HEVC_NAL_IDR_N_LP : return "IDR_N_LP"; |
| case HEVC_NAL_CRA_NUT : return "CRA_NUT"; |
| case HEVC_NAL_VPS : return "VPS"; |
| case HEVC_NAL_SPS : return "SPS"; |
| case HEVC_NAL_PPS : return "PPS"; |
| case HEVC_NAL_AUD : return "AUD"; |
| case HEVC_NAL_EOS_NUT : return "EOS_NUT"; |
| case HEVC_NAL_EOB_NUT : return "EOB_NUT"; |
| case HEVC_NAL_FD_NUT : return "FD_NUT"; |
| case HEVC_NAL_SEI_PREFIX : return "SEI_PREFIX"; |
| case HEVC_NAL_SEI_SUFFIX : return "SEI_SUFFIX"; |
| default : return "?"; |
| } |
| } |
| |
| static int get_bit_length(H2645NAL *nal, int skip_trailing_zeros) |
| { |
| int size = nal->size; |
| int v; |
| |
| while (skip_trailing_zeros && size > 0 && nal->data[size - 1] == 0) |
| size--; |
| |
| if (!size) |
| return 0; |
| |
| v = nal->data[size - 1]; |
| |
| if (size > INT_MAX / 8) |
| return AVERROR(ERANGE); |
| size *= 8; |
| |
| /* remove the stop bit and following trailing zeros, |
| * or nothing for damaged bitstreams */ |
| if (v) |
| size -= ff_ctz(v) + 1; |
| |
| return size; |
| } |
| |
| /** |
| * @return AVERROR_INVALIDDATA if the packet is not a valid NAL unit, |
| * 0 if the unit should be skipped, 1 otherwise |
| */ |
| static int hevc_parse_nal_header(H2645NAL *nal, void *logctx) |
| { |
| 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(logctx, 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; |
| } |
| |
| static int h264_parse_nal_header(H2645NAL *nal, void *logctx) |
| { |
| GetBitContext *gb = &nal->gb; |
| |
| if (get_bits1(gb) != 0) |
| return AVERROR_INVALIDDATA; |
| |
| nal->ref_idc = get_bits(gb, 2); |
| nal->type = get_bits(gb, 5); |
| |
| av_log(logctx, AV_LOG_DEBUG, |
| "nal_unit_type: %d, nal_ref_idc: %d\n", |
| nal->type, nal->ref_idc); |
| |
| return 1; |
| } |
| |
| int ff_h2645_packet_split(H2645Packet *pkt, const uint8_t *buf, int length, |
| void *logctx, int is_nalff, int nal_length_size, |
| enum AVCodecID codec_id, int small_padding) |
| { |
| int consumed, ret = 0; |
| const uint8_t *next_avc = is_nalff ? buf : buf + length; |
| |
| pkt->nb_nals = 0; |
| while (length >= 4) { |
| H2645NAL *nal; |
| int extract_length = 0; |
| int skip_trailing_zeros = 1; |
| |
| if (buf == next_avc) { |
| int i = 0; |
| extract_length = get_nalsize(nal_length_size, |
| buf, length, &i, logctx); |
| if (extract_length < 0) |
| return extract_length; |
| |
| buf += nal_length_size; |
| length -= nal_length_size; |
| |
| next_avc = buf + extract_length; |
| } else { |
| if (buf > next_avc) |
| av_log(logctx, AV_LOG_WARNING, "Exceeded next NALFF position, re-syncing.\n"); |
| |
| /* 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(logctx, AV_LOG_ERROR, "No start code is found.\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| } else if (buf >= (next_avc - 3)) |
| break; |
| } |
| |
| buf += 3; |
| length -= 3; |
| extract_length = FFMIN(length, next_avc - buf); |
| |
| if (buf >= next_avc) { |
| /* skip to the start of the next NAL */ |
| int offset = next_avc - buf; |
| buf += offset; |
| length -= offset; |
| continue; |
| } |
| } |
| |
| 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_h2645_extract_rbsp(buf, extract_length, nal, small_padding); |
| if (consumed < 0) |
| return consumed; |
| |
| if (is_nalff && (extract_length != consumed) && extract_length) |
| av_log(logctx, AV_LOG_DEBUG, |
| "NALFF: Consumed only %d bytes instead of %d\n", |
| consumed, extract_length); |
| |
| pkt->nb_nals++; |
| |
| /* see commit 3566042a0 */ |
| if (consumed < length - 3 && |
| buf[consumed] == 0x00 && buf[consumed + 1] == 0x00 && |
| buf[consumed + 2] == 0x01 && buf[consumed + 3] == 0xE0) |
| skip_trailing_zeros = 0; |
| |
| nal->size_bits = get_bit_length(nal, skip_trailing_zeros); |
| |
| ret = init_get_bits(&nal->gb, nal->data, nal->size_bits); |
| if (ret < 0) |
| return ret; |
| |
| if (codec_id == AV_CODEC_ID_HEVC) |
| ret = hevc_parse_nal_header(nal, logctx); |
| else |
| ret = h264_parse_nal_header(nal, logctx); |
| if (ret <= 0 || nal->size <= 0) { |
| if (ret < 0) { |
| av_log(logctx, AV_LOG_ERROR, "Invalid NAL unit %d, skipping.\n", |
| nal->type); |
| } |
| pkt->nb_nals--; |
| } |
| |
| buf += consumed; |
| length -= consumed; |
| } |
| |
| return 0; |
| } |
| |
| void ff_h2645_packet_uninit(H2645Packet *pkt) |
| { |
| int i; |
| for (i = 0; i < pkt->nals_allocated; i++) { |
| av_freep(&pkt->nals[i].rbsp_buffer); |
| av_freep(&pkt->nals[i].skipped_bytes_pos); |
| } |
| av_freep(&pkt->nals); |
| pkt->nals_allocated = 0; |
| } |
