FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavformat/rtpdec_amr.c
Date: 2022-12-06 04:36:11
Exec Total Coverage
Lines: 0 66 0.0%
Functions: 0 4 0.0%
Branches: 0 42 0.0%

Line Branch Exec Source
1 /*
2 * RTP AMR Depacketizer, RFC 3267
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 "libavutil/channel_layout.h"
23 #include "avformat.h"
24 #include "rtpdec_formats.h"
25 #include "libavutil/avstring.h"
26
27 static const uint8_t frame_sizes_nb[16] = {
28 12, 13, 15, 17, 19, 20, 26, 31, 5, 0, 0, 0, 0, 0, 0, 0
29 };
30 static const uint8_t frame_sizes_wb[16] = {
31 17, 23, 32, 36, 40, 46, 50, 58, 60, 5, 5, 0, 0, 0, 0, 0
32 };
33
34 struct PayloadContext {
35 int octet_align;
36 int crc;
37 int interleaving;
38 int channels;
39 };
40
41 static av_cold int amr_init(AVFormatContext *s, int st_index, PayloadContext *data)
42 {
43 data->channels = 1;
44 return 0;
45 }
46
47 static int amr_handle_packet(AVFormatContext *ctx, PayloadContext *data,
48 AVStream *st, AVPacket *pkt, uint32_t *timestamp,
49 const uint8_t *buf, int len, uint16_t seq,
50 int flags)
51 {
52 const uint8_t *frame_sizes = NULL;
53 int frames;
54 int i, ret;
55 const uint8_t *speech_data;
56 uint8_t *ptr;
57
58 if (st->codecpar->codec_id == AV_CODEC_ID_AMR_NB) {
59 frame_sizes = frame_sizes_nb;
60 } else if (st->codecpar->codec_id == AV_CODEC_ID_AMR_WB) {
61 frame_sizes = frame_sizes_wb;
62 } else {
63 av_log(ctx, AV_LOG_ERROR, "Bad codec ID\n");
64 return AVERROR_INVALIDDATA;
65 }
66
67 if (st->codecpar->ch_layout.nb_channels != 1) {
68 av_log(ctx, AV_LOG_ERROR, "Only mono AMR is supported\n");
69 return AVERROR_INVALIDDATA;
70 }
71 av_channel_layout_default(&st->codecpar->ch_layout, 1);
72
73 /* The AMR RTP packet consists of one header byte, followed
74 * by one TOC byte for each AMR frame in the packet, followed
75 * by the speech data for all the AMR frames.
76 *
77 * The header byte contains only a codec mode request, for
78 * requesting what kind of AMR data the sender wants to
79 * receive. Not used at the moment.
80 */
81
82 /* Count the number of frames in the packet. The highest bit
83 * is set in a TOC byte if there are more frames following.
84 */
85 for (frames = 1; frames < len && (buf[frames] & 0x80); frames++) ;
86
87 if (1 + frames >= len) {
88 /* We hit the end of the packet while counting frames. */
89 av_log(ctx, AV_LOG_ERROR, "No speech data found\n");
90 return AVERROR_INVALIDDATA;
91 }
92
93 speech_data = buf + 1 + frames;
94
95 /* Everything except the codec mode request byte should be output. */
96 if ((ret = av_new_packet(pkt, len - 1)) < 0) {
97 av_log(ctx, AV_LOG_ERROR, "Out of memory\n");
98 return ret;
99 }
100 pkt->stream_index = st->index;
101 ptr = pkt->data;
102
103 for (i = 0; i < frames; i++) {
104 uint8_t toc = buf[1 + i];
105 int frame_size = frame_sizes[(toc >> 3) & 0x0f];
106
107 if (speech_data + frame_size > buf + len) {
108 /* Too little speech data */
109 av_log(ctx, AV_LOG_WARNING, "Too little speech data in the RTP packet\n");
110 /* Set the unwritten part of the packet to zero. */
111 memset(ptr, 0, pkt->data + pkt->size - ptr);
112 pkt->size = ptr - pkt->data;
113 return 0;
114 }
115
116 /* Extract the AMR frame mode from the TOC byte */
117 *ptr++ = toc & 0x7C;
118
119 /* Copy the speech data */
120 memcpy(ptr, speech_data, frame_size);
121 speech_data += frame_size;
122 ptr += frame_size;
123 }
124
125 if (speech_data < buf + len) {
126 av_log(ctx, AV_LOG_WARNING, "Too much speech data in the RTP packet?\n");
127 /* Set the unwritten part of the packet to zero. */
128 memset(ptr, 0, pkt->data + pkt->size - ptr);
129 pkt->size = ptr - pkt->data;
130 }
131
132 return 0;
133 }
134
135 static int amr_parse_fmtp(AVFormatContext *s,
136 AVStream *stream, PayloadContext *data,
137 const char *attr, const char *value)
138 {
139 /* Some AMR SDP configurations contain "octet-align", without
140 * the trailing =1. Therefore, if the value is empty,
141 * interpret it as "1".
142 */
143 if (!strcmp(value, "")) {
144 av_log(s, AV_LOG_WARNING, "AMR fmtp attribute %s had "
145 "nonstandard empty value\n", attr);
146 value = "1";
147 }
148 if (!strcmp(attr, "octet-align"))
149 data->octet_align = atoi(value);
150 else if (!strcmp(attr, "crc"))
151 data->crc = atoi(value);
152 else if (!strcmp(attr, "interleaving"))
153 data->interleaving = atoi(value);
154 else if (!strcmp(attr, "channels"))
155 data->channels = atoi(value);
156 return 0;
157 }
158
159 static int amr_parse_sdp_line(AVFormatContext *s, int st_index,
160 PayloadContext *data, const char *line)
161 {
162 const char *p;
163 int ret;
164
165 if (st_index < 0)
166 return 0;
167
168 /* Parse an fmtp line this one:
169 * a=fmtp:97 octet-align=1; interleaving=0
170 * That is, a normal fmtp: line followed by semicolon & space
171 * separated key/value pairs.
172 */
173 if (av_strstart(line, "fmtp:", &p)) {
174 ret = ff_parse_fmtp(s, s->streams[st_index], data, p, amr_parse_fmtp);
175 if (!data->octet_align || data->crc ||
176 data->interleaving || data->channels != 1) {
177 av_log(s, AV_LOG_ERROR, "Unsupported RTP/AMR configuration!\n");
178 return -1;
179 }
180 return ret;
181 }
182 return 0;
183 }
184
185 const RTPDynamicProtocolHandler ff_amr_nb_dynamic_handler = {
186 .enc_name = "AMR",
187 .codec_type = AVMEDIA_TYPE_AUDIO,
188 .codec_id = AV_CODEC_ID_AMR_NB,
189 .priv_data_size = sizeof(PayloadContext),
190 .init = amr_init,
191 .parse_sdp_a_line = amr_parse_sdp_line,
192 .parse_packet = amr_handle_packet,
193 };
194
195 const RTPDynamicProtocolHandler ff_amr_wb_dynamic_handler = {
196 .enc_name = "AMR-WB",
197 .codec_type = AVMEDIA_TYPE_AUDIO,
198 .codec_id = AV_CODEC_ID_AMR_WB,
199 .priv_data_size = sizeof(PayloadContext),
200 .init = amr_init,
201 .parse_sdp_a_line = amr_parse_sdp_line,
202 .parse_packet = amr_handle_packet,
203 };
204