| Line | Branch | Exec | Source |
|---|---|---|---|
| 1 | /* | ||
| 2 | * RTP H.263 Depacketizer, RFC 4629 | ||
| 3 | * Copyright (c) 2010 Martin Storsjo | ||
| 4 | * | ||
| 5 | * This file is part of FFmpeg. | ||
| 6 | * | ||
| 7 | * FFmpeg is free software; you can redistribute it and/or | ||
| 8 | * modify it under the terms of the GNU Lesser General Public | ||
| 9 | * License as published by the Free Software Foundation; either | ||
| 10 | * version 2.1 of the License, or (at your option) any later version. | ||
| 11 | * | ||
| 12 | * FFmpeg is distributed in the hope that it will be useful, | ||
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
| 15 | * Lesser General Public License for more details. | ||
| 16 | * | ||
| 17 | * You should have received a copy of the GNU Lesser General Public | ||
| 18 | * License along with FFmpeg; if not, write to the Free Software | ||
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | ||
| 20 | */ | ||
| 21 | |||
| 22 | #include "avformat.h" | ||
| 23 | #include "rtpdec_formats.h" | ||
| 24 | #include "libavutil/attributes.h" | ||
| 25 | #include "libavutil/intreadwrite.h" | ||
| 26 | |||
| 27 | ✗ | int ff_h263_handle_packet(AVFormatContext *ctx, PayloadContext *data, | |
| 28 | AVStream *st, AVPacket *pkt, uint32_t *timestamp, | ||
| 29 | const uint8_t *buf, int len, uint16_t seq, int flags) | ||
| 30 | { | ||
| 31 | uint8_t *ptr; | ||
| 32 | uint16_t header; | ||
| 33 | int startcode, vrc, picture_header, ret; | ||
| 34 | |||
| 35 | ✗ | if (len < 2) { | |
| 36 | ✗ | av_log(ctx, AV_LOG_ERROR, "Too short H.263 RTP packet\n"); | |
| 37 | ✗ | return AVERROR_INVALIDDATA; | |
| 38 | } | ||
| 39 | |||
| 40 | /* Decode the 16 bit H.263+ payload header, as described in section | ||
| 41 | * 5.1 of RFC 4629. The fields of this header are: | ||
| 42 | * - 5 reserved bits, should be ignored. | ||
| 43 | * - One bit (P, startcode), indicating a picture start, picture segment | ||
| 44 | * start or video sequence end. If set, two zero bytes should be | ||
| 45 | * prepended to the payload. | ||
| 46 | * - One bit (V, vrc), indicating the presence of an 8 bit Video | ||
| 47 | * Redundancy Coding field after this 16 bit header. | ||
| 48 | * - 6 bits (PLEN, picture_header), the length (in bytes) of an extra | ||
| 49 | * picture header, following the VRC field. | ||
| 50 | * - 3 bits (PEBIT), the number of bits to ignore of the last byte | ||
| 51 | * of the extra picture header. (Not used at the moment.) | ||
| 52 | */ | ||
| 53 | ✗ | header = AV_RB16(buf); | |
| 54 | ✗ | startcode = (header & 0x0400) >> 9; | |
| 55 | ✗ | vrc = header & 0x0200; | |
| 56 | ✗ | picture_header = (header & 0x01f8) >> 3; | |
| 57 | ✗ | buf += 2; | |
| 58 | ✗ | len -= 2; | |
| 59 | |||
| 60 | ✗ | if (vrc) { | |
| 61 | /* Skip VRC header if present, not used at the moment. */ | ||
| 62 | ✗ | buf += 1; | |
| 63 | ✗ | len -= 1; | |
| 64 | } | ||
| 65 | ✗ | if (picture_header) { | |
| 66 | /* Skip extra picture header if present, not used at the moment. */ | ||
| 67 | ✗ | buf += picture_header; | |
| 68 | ✗ | len -= picture_header; | |
| 69 | } | ||
| 70 | |||
| 71 | ✗ | if (len < 0) { | |
| 72 | ✗ | av_log(ctx, AV_LOG_ERROR, "Too short H.263 RTP packet\n"); | |
| 73 | ✗ | return AVERROR_INVALIDDATA; | |
| 74 | } | ||
| 75 | |||
| 76 | ✗ | if ((ret = av_new_packet(pkt, len + startcode)) < 0) { | |
| 77 | ✗ | av_log(ctx, AV_LOG_ERROR, "Out of memory\n"); | |
| 78 | ✗ | return ret; | |
| 79 | } | ||
| 80 | ✗ | pkt->stream_index = st->index; | |
| 81 | ✗ | ptr = pkt->data; | |
| 82 | |||
| 83 | ✗ | if (startcode) { | |
| 84 | ✗ | *ptr++ = 0; | |
| 85 | ✗ | *ptr++ = 0; | |
| 86 | } | ||
| 87 | ✗ | memcpy(ptr, buf, len); | |
| 88 | |||
| 89 | ✗ | return 0; | |
| 90 | } | ||
| 91 | |||
| 92 | const RTPDynamicProtocolHandler ff_h263_1998_dynamic_handler = { | ||
| 93 | .enc_name = "H263-1998", | ||
| 94 | .codec_type = AVMEDIA_TYPE_VIDEO, | ||
| 95 | .codec_id = AV_CODEC_ID_H263, | ||
| 96 | .need_parsing = AVSTREAM_PARSE_FULL, | ||
| 97 | .parse_packet = ff_h263_handle_packet, | ||
| 98 | }; | ||
| 99 | |||
| 100 | const RTPDynamicProtocolHandler ff_h263_2000_dynamic_handler = { | ||
| 101 | .enc_name = "H263-2000", | ||
| 102 | .codec_type = AVMEDIA_TYPE_VIDEO, | ||
| 103 | .codec_id = AV_CODEC_ID_H263, | ||
| 104 | .need_parsing = AVSTREAM_PARSE_FULL, | ||
| 105 | .parse_packet = ff_h263_handle_packet, | ||
| 106 | }; | ||
| 107 |