| /* |
| * 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 "avformat.h" |
| #include "avio.h" |
| |
| const uint8_t *ff_avc_find_startcode(const uint8_t *p, const uint8_t *end) |
| { |
| const uint8_t *a = p + 4 - ((long)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-1; |
| if( p[2] == 0 && p[3] == 1 ) |
| return p; |
| } |
| if( p[3] == 0 ) { |
| if( p[2] == 0 && p[4] == 1 ) |
| return p+1; |
| if( p[4] == 0 && p[5] == 1 ) |
| return p+2; |
| } |
| } |
| } |
| |
| for( end += 3; p < end; p++ ) { |
| if( p[0] == 0 && p[1] == 0 && p[2] == 1 ) |
| return p; |
| } |
| |
| return end + 3; |
| } |
| |
| int ff_avc_parse_nal_units(ByteIOContext *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); |
| while (nal_start < end) { |
| while(!*(nal_start++)); |
| nal_end = ff_avc_find_startcode(nal_start, end); |
| put_be32(pb, nal_end - nal_start); |
| put_buffer(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) |
| { |
| ByteIOContext *pb; |
| int ret = url_open_dyn_buf(&pb); |
| if(ret < 0) |
| return ret; |
| |
| ff_avc_parse_nal_units(pb, buf_in, *size); |
| |
| av_freep(buf); |
| *size = url_close_dyn_buf(pb, buf); |
| return 0; |
| } |
| |
| int ff_isom_write_avcc(ByteIOContext *pb, const uint8_t *data, int len) |
| { |
| if (len > 6) { |
| /* check for h264 start code */ |
| if (AV_RB32(data) == 0x00000001 || |
| AV_RB24(data) == 0x000001) { |
| uint8_t *buf=NULL, *end, *start; |
| uint32_t sps_size=0, pps_size=0; |
| uint8_t *sps=0, *pps=0; |
| |
| int ret = ff_avc_parse_nal_units_buf(data, &buf, &len); |
| if (ret < 0) |
| return ret; |
| start = buf; |
| end = buf + len; |
| |
| /* look for sps and pps */ |
| while (buf < end) { |
| unsigned int size; |
| uint8_t nal_type; |
| size = AV_RB32(buf); |
| nal_type = buf[4] & 0x1f; |
| if (nal_type == 7) { /* SPS */ |
| sps = buf + 4; |
| sps_size = size; |
| } else if (nal_type == 8) { /* PPS */ |
| pps = buf + 4; |
| pps_size = size; |
| } |
| buf += size + 4; |
| } |
| assert(sps); |
| assert(pps); |
| |
| put_byte(pb, 1); /* version */ |
| put_byte(pb, sps[1]); /* profile */ |
| put_byte(pb, sps[2]); /* profile compat */ |
| put_byte(pb, sps[3]); /* level */ |
| put_byte(pb, 0xff); /* 6 bits reserved (111111) + 2 bits nal size length - 1 (11) */ |
| put_byte(pb, 0xe1); /* 3 bits reserved (111) + 5 bits number of sps (00001) */ |
| |
| put_be16(pb, sps_size); |
| put_buffer(pb, sps, sps_size); |
| put_byte(pb, 1); /* number of pps */ |
| put_be16(pb, pps_size); |
| put_buffer(pb, pps, pps_size); |
| av_free(start); |
| } else { |
| put_buffer(pb, data, len); |
| } |
| } |
| return 0; |
| } |