| /* |
| * HEVC MP4 to Annex B byte stream format filter |
| * copyright (c) 2015 Anton Khirnov |
| * |
| * 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 "libavutil/intreadwrite.h" |
| #include "libavutil/mem.h" |
| |
| #include "avcodec.h" |
| #include "bsf.h" |
| #include "bsf_internal.h" |
| #include "bytestream.h" |
| #include "hevc.h" |
| |
| #define MIN_HEVCC_LENGTH 23 |
| |
| typedef struct HEVCBSFContext { |
| uint8_t length_size; |
| int extradata_parsed; |
| } HEVCBSFContext; |
| |
| static int hevc_extradata_to_annexb(AVBSFContext *ctx) |
| { |
| GetByteContext gb; |
| int length_size, num_arrays, i, j; |
| int ret = 0; |
| |
| uint8_t *new_extradata = NULL; |
| size_t new_extradata_size = 0; |
| |
| bytestream2_init(&gb, ctx->par_in->extradata, ctx->par_in->extradata_size); |
| |
| bytestream2_skip(&gb, 21); |
| length_size = (bytestream2_get_byte(&gb) & 3) + 1; |
| num_arrays = bytestream2_get_byte(&gb); |
| |
| for (i = 0; i < num_arrays; i++) { |
| int type = bytestream2_get_byte(&gb) & 0x3f; |
| int cnt = bytestream2_get_be16(&gb); |
| |
| if (!(type == HEVC_NAL_VPS || type == HEVC_NAL_SPS || type == HEVC_NAL_PPS || |
| type == HEVC_NAL_SEI_PREFIX || type == HEVC_NAL_SEI_SUFFIX)) { |
| av_log(ctx, AV_LOG_ERROR, "Invalid NAL unit type in extradata: %d\n", |
| type); |
| ret = AVERROR_INVALIDDATA; |
| goto fail; |
| } |
| |
| for (j = 0; j < cnt; j++) { |
| int nalu_len = bytestream2_get_be16(&gb); |
| |
| if (4 + AV_INPUT_BUFFER_PADDING_SIZE + nalu_len > SIZE_MAX - new_extradata_size) { |
| ret = AVERROR_INVALIDDATA; |
| goto fail; |
| } |
| ret = av_reallocp(&new_extradata, new_extradata_size + nalu_len + 4 + AV_INPUT_BUFFER_PADDING_SIZE); |
| if (ret < 0) |
| goto fail; |
| |
| AV_WB32(new_extradata + new_extradata_size, 1); // add the startcode |
| bytestream2_get_buffer(&gb, new_extradata + new_extradata_size + 4, nalu_len); |
| new_extradata_size += 4 + nalu_len; |
| memset(new_extradata + new_extradata_size, 0, AV_INPUT_BUFFER_PADDING_SIZE); |
| } |
| } |
| |
| av_freep(&ctx->par_out->extradata); |
| ctx->par_out->extradata = new_extradata; |
| ctx->par_out->extradata_size = new_extradata_size; |
| |
| if (!new_extradata_size) |
| av_log(ctx, AV_LOG_WARNING, "No parameter sets in the extradata\n"); |
| |
| return length_size; |
| fail: |
| av_freep(&new_extradata); |
| return ret; |
| } |
| |
| static int hevc_mp4toannexb_init(AVBSFContext *ctx) |
| { |
| HEVCBSFContext *s = ctx->priv_data; |
| int ret; |
| |
| if (ctx->par_in->extradata_size < MIN_HEVCC_LENGTH || |
| AV_RB24(ctx->par_in->extradata) == 1 || |
| AV_RB32(ctx->par_in->extradata) == 1) { |
| av_log(ctx, AV_LOG_VERBOSE, |
| "The input looks like it is Annex B already\n"); |
| } else { |
| ret = hevc_extradata_to_annexb(ctx); |
| if (ret < 0) |
| return ret; |
| s->length_size = ret; |
| s->extradata_parsed = 1; |
| } |
| |
| return 0; |
| } |
| |
| static int hevc_mp4toannexb_filter(AVBSFContext *ctx, AVPacket *out) |
| { |
| HEVCBSFContext *s = ctx->priv_data; |
| AVPacket *in; |
| GetByteContext gb; |
| |
| int got_irap = 0; |
| int i, ret = 0; |
| |
| ret = ff_bsf_get_packet(ctx, &in); |
| if (ret < 0) |
| return ret; |
| |
| if (!s->extradata_parsed) { |
| av_packet_move_ref(out, in); |
| av_packet_free(&in); |
| return 0; |
| } |
| |
| bytestream2_init(&gb, in->data, in->size); |
| |
| while (bytestream2_get_bytes_left(&gb)) { |
| uint32_t nalu_size = 0; |
| int nalu_type; |
| int is_irap, add_extradata, extra_size, prev_size; |
| |
| if (bytestream2_get_bytes_left(&gb) < s->length_size) { |
| ret = AVERROR_INVALIDDATA; |
| goto fail; |
| } |
| for (i = 0; i < s->length_size; i++) |
| nalu_size = (nalu_size << 8) | bytestream2_get_byte(&gb); |
| |
| if (nalu_size < 2 || nalu_size > bytestream2_get_bytes_left(&gb)) { |
| ret = AVERROR_INVALIDDATA; |
| goto fail; |
| } |
| |
| nalu_type = (bytestream2_peek_byte(&gb) >> 1) & 0x3f; |
| |
| /* prepend extradata to IRAP frames */ |
| is_irap = nalu_type >= 16 && nalu_type <= 23; |
| add_extradata = is_irap && !got_irap; |
| extra_size = add_extradata * ctx->par_out->extradata_size; |
| got_irap |= is_irap; |
| |
| if (FFMIN(INT_MAX, SIZE_MAX) < 4ULL + nalu_size + extra_size) { |
| ret = AVERROR_INVALIDDATA; |
| goto fail; |
| } |
| |
| prev_size = out->size; |
| |
| ret = av_grow_packet(out, 4 + nalu_size + extra_size); |
| if (ret < 0) |
| goto fail; |
| |
| if (extra_size) |
| memcpy(out->data + prev_size, ctx->par_out->extradata, extra_size); |
| AV_WB32(out->data + prev_size + extra_size, 1); |
| bytestream2_get_buffer(&gb, out->data + prev_size + 4 + extra_size, nalu_size); |
| } |
| |
| ret = av_packet_copy_props(out, in); |
| if (ret < 0) |
| goto fail; |
| |
| fail: |
| if (ret < 0) |
| av_packet_unref(out); |
| av_packet_free(&in); |
| |
| return ret; |
| } |
| |
| static const enum AVCodecID codec_ids[] = { |
| AV_CODEC_ID_HEVC, AV_CODEC_ID_NONE, |
| }; |
| |
| const AVBitStreamFilter ff_hevc_mp4toannexb_bsf = { |
| .name = "hevc_mp4toannexb", |
| .priv_data_size = sizeof(HEVCBSFContext), |
| .init = hevc_mp4toannexb_init, |
| .filter = hevc_mp4toannexb_filter, |
| .codec_ids = codec_ids, |
| }; |