| /* |
| * AVC helper functions for muxers |
| * Copyright (c) 2006 Baptiste Coudurier <baptiste.coudurier@smartjog.com> |
| * |
| * 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 "libavutil/intreadwrite.h" |
| #include "libavcodec/h264.h" |
| #include "avformat.h" |
| #include "avio.h" |
| #include "avc.h" |
| |
| static const uint8_t *ff_avc_find_startcode_internal(const uint8_t *p, const uint8_t *end) |
| { |
| const uint8_t *a = p + 4 - ((intptr_t)p & 3); |
| |
| for (end -= 3; p < a && p < end; p++) { |
| if (p[0] == 0 && p[1] == 0 && p[2] == 1) |
| return p; |
| } |
| |
| for (end -= 3; p < end; p += 4) { |
| uint32_t x = *(const uint32_t*)p; |
| // if ((x - 0x01000100) & (~x) & 0x80008000) // little endian |
| // if ((x - 0x00010001) & (~x) & 0x00800080) // big endian |
| if ((x - 0x01010101) & (~x) & 0x80808080) { // generic |
| if (p[1] == 0) { |
| if (p[0] == 0 && p[2] == 1) |
| return p; |
| if (p[2] == 0 && p[3] == 1) |
| return p+1; |
| } |
| if (p[3] == 0) { |
| if (p[2] == 0 && p[4] == 1) |
| return p+2; |
| if (p[4] == 0 && p[5] == 1) |
| return p+3; |
| } |
| } |
| } |
| |
| for (end += 3; p < end; p++) { |
| if (p[0] == 0 && p[1] == 0 && p[2] == 1) |
| return p; |
| } |
| |
| return end + 3; |
| } |
| |
| const uint8_t *ff_avc_find_startcode(const uint8_t *p, const uint8_t *end){ |
| const uint8_t *out= ff_avc_find_startcode_internal(p, end); |
| if(p<out && out<end && !out[-1]) out--; |
| return out; |
| } |
| |
| int ff_avc_parse_nal_units(AVIOContext *pb, const uint8_t *buf_in, int size) |
| { |
| const uint8_t *p = buf_in; |
| const uint8_t *end = p + size; |
| const uint8_t *nal_start, *nal_end; |
| |
| size = 0; |
| nal_start = ff_avc_find_startcode(p, end); |
| for (;;) { |
| while (nal_start < end && !*(nal_start++)); |
| if (nal_start == end) |
| break; |
| |
| nal_end = ff_avc_find_startcode(nal_start, end); |
| avio_wb32(pb, nal_end - nal_start); |
| avio_write(pb, nal_start, nal_end - nal_start); |
| size += 4 + nal_end - nal_start; |
| nal_start = nal_end; |
| } |
| return size; |
| } |
| |
| int ff_avc_parse_nal_units_buf(const uint8_t *buf_in, uint8_t **buf, int *size) |
| { |
| AVIOContext *pb; |
| int ret = avio_open_dyn_buf(&pb); |
| if(ret < 0) |
| return ret; |
| |
| ff_avc_parse_nal_units(pb, buf_in, *size); |
| |
| av_freep(buf); |
| *size = avio_close_dyn_buf(pb, buf); |
| return 0; |
| } |
| |
| int ff_isom_write_avcc(AVIOContext *pb, const uint8_t *data, int len) |
| { |
| AVIOContext *sps_pb = NULL, *pps_pb = NULL; |
| uint8_t *buf = NULL, *end, *start = NULL; |
| uint8_t *sps = NULL, *pps = NULL; |
| uint32_t sps_size = 0, pps_size = 0; |
| int ret, nb_sps = 0, nb_pps = 0; |
| |
| if (len <= 6) |
| return AVERROR_INVALIDDATA; |
| |
| /* check for H.264 start code */ |
| if (AV_RB32(data) != 0x00000001 && |
| AV_RB24(data) != 0x000001) { |
| avio_write(pb, data, len); |
| return 0; |
| } |
| |
| ret = ff_avc_parse_nal_units_buf(data, &buf, &len); |
| if (ret < 0) |
| return ret; |
| start = buf; |
| end = buf + len; |
| |
| ret = avio_open_dyn_buf(&sps_pb); |
| if (ret < 0) |
| goto fail; |
| ret = avio_open_dyn_buf(&pps_pb); |
| if (ret < 0) |
| goto fail; |
| |
| /* look for sps and pps */ |
| while (end - buf > 4) { |
| uint32_t size; |
| uint8_t nal_type; |
| size = FFMIN(AV_RB32(buf), end - buf - 4); |
| buf += 4; |
| nal_type = buf[0] & 0x1f; |
| |
| if (nal_type == 7) { /* SPS */ |
| nb_sps++; |
| if (size > UINT16_MAX || nb_sps >= H264_MAX_SPS_COUNT) { |
| ret = AVERROR_INVALIDDATA; |
| goto fail; |
| } |
| avio_wb16(sps_pb, size); |
| avio_write(sps_pb, buf, size); |
| } else if (nal_type == 8) { /* PPS */ |
| nb_pps++; |
| if (size > UINT16_MAX || nb_pps >= H264_MAX_PPS_COUNT) { |
| ret = AVERROR_INVALIDDATA; |
| goto fail; |
| } |
| avio_wb16(pps_pb, size); |
| avio_write(pps_pb, buf, size); |
| } |
| |
| buf += size; |
| } |
| sps_size = avio_close_dyn_buf(sps_pb, &sps); |
| pps_size = avio_close_dyn_buf(pps_pb, &pps); |
| |
| if (sps_size < 6 || !pps_size) { |
| ret = AVERROR_INVALIDDATA; |
| goto fail; |
| } |
| |
| avio_w8(pb, 1); /* version */ |
| avio_w8(pb, sps[3]); /* profile */ |
| avio_w8(pb, sps[4]); /* profile compat */ |
| avio_w8(pb, sps[5]); /* level */ |
| avio_w8(pb, 0xff); /* 6 bits reserved (111111) + 2 bits nal size length - 1 (11) */ |
| avio_w8(pb, 0xe0 | nb_sps); /* 3 bits reserved (111) + 5 bits number of sps */ |
| |
| avio_write(pb, sps, sps_size); |
| avio_w8(pb, nb_pps); /* number of pps */ |
| avio_write(pb, pps, pps_size); |
| |
| fail: |
| if (!sps) |
| avio_close_dyn_buf(sps_pb, &sps); |
| if (!pps) |
| avio_close_dyn_buf(pps_pb, &pps); |
| av_free(sps); |
| av_free(pps); |
| av_free(start); |
| |
| return ret; |
| } |
| |
| int ff_avc_write_annexb_extradata(const uint8_t *in, uint8_t **buf, int *size) |
| { |
| uint16_t sps_size, pps_size; |
| uint8_t *out; |
| int out_size; |
| |
| *buf = NULL; |
| if (*size >= 4 && (AV_RB32(in) == 0x00000001 || AV_RB24(in) == 0x000001)) |
| return 0; |
| if (*size < 11 || in[0] != 1) |
| return AVERROR_INVALIDDATA; |
| |
| sps_size = AV_RB16(&in[6]); |
| if (11 + sps_size > *size) |
| return AVERROR_INVALIDDATA; |
| pps_size = AV_RB16(&in[9 + sps_size]); |
| if (11 + sps_size + pps_size > *size) |
| return AVERROR_INVALIDDATA; |
| out_size = 8 + sps_size + pps_size; |
| out = av_mallocz(out_size + AV_INPUT_BUFFER_PADDING_SIZE); |
| if (!out) |
| return AVERROR(ENOMEM); |
| AV_WB32(&out[0], 0x00000001); |
| memcpy(out + 4, &in[8], sps_size); |
| AV_WB32(&out[4 + sps_size], 0x00000001); |
| memcpy(out + 8 + sps_size, &in[11 + sps_size], pps_size); |
| *buf = out; |
| *size = out_size; |
| return 0; |
| } |
| |
| const uint8_t *ff_avc_mp4_find_startcode(const uint8_t *start, |
| const uint8_t *end, |
| int nal_length_size) |
| { |
| unsigned int res = 0; |
| |
| if (end - start < nal_length_size) |
| return NULL; |
| while (nal_length_size--) |
| res = (res << 8) | *start++; |
| |
| if (res > end - start) |
| return NULL; |
| |
| return start + res; |
| } |
