Lego Mindstorms RSO muxer and demuxer.
[libav.git] / libavformat / rsoenc.c
1 /*
2 * RSO muxer
3 * Copyright (c) 2001 Fabrice Bellard (original AU code)
4 * Copyright (c) 2010 Rafael Carre
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23 #include "avformat.h"
24 #include "internal.h"
25 #include "riff.h"
26 #include "rso.h"
27
28 static int rso_write_header(AVFormatContext *s)
29 {
30 ByteIOContext *pb = s->pb;
31 AVCodecContext *enc = s->streams[0]->codec;
32
33 if (!enc->codec_tag)
34 return AVERROR_INVALIDDATA;
35
36 if (enc->channels != 1) {
37 av_log(s, AV_LOG_ERROR, "RSO only supports mono\n");
38 return AVERROR_INVALIDDATA;
39 }
40
41 if (url_is_streamed(s->pb)) {
42 av_log(s, AV_LOG_ERROR, "muxer does not support non seekable output\n");
43 return AVERROR_INVALIDDATA;
44 }
45
46 /* XXX: find legal sample rates (if any) */
47 if (enc->sample_rate >= 1u<<16) {
48 av_log(s, AV_LOG_ERROR, "Sample rate must be < 65536\n");
49 return AVERROR_INVALIDDATA;
50 }
51
52 if (enc->codec_id == CODEC_ID_ADPCM_IMA_WAV) {
53 av_log(s, AV_LOG_ERROR, "ADPCM in RSO not implemented\n");
54 return AVERROR_PATCHWELCOME;
55 }
56
57 /* format header */
58 put_be16(pb, enc->codec_tag); /* codec ID */
59 put_be16(pb, 0); /* data size, will be written at EOF */
60 put_be16(pb, enc->sample_rate);
61 put_be16(pb, 0x0000); /* play mode ? (0x0000 = don't loop) */
62
63 put_flush_packet(pb);
64
65 return 0;
66 }
67
68 static int rso_write_packet(AVFormatContext *s, AVPacket *pkt)
69 {
70 put_buffer(s->pb, pkt->data, pkt->size);
71 return 0;
72 }
73
74 static int rso_write_trailer(AVFormatContext *s)
75 {
76 ByteIOContext *pb = s->pb;
77 int64_t file_size;
78 uint16_t coded_file_size;
79
80 file_size = url_ftell(pb);
81
82 if (file_size < 0)
83 return file_size;
84
85 if (file_size > 0xffff + RSO_HEADER_SIZE) {
86 av_log(s, AV_LOG_WARNING,
87 "Output file is too big (%"PRId64" bytes >= 64kB)\n", file_size);
88 coded_file_size = 0xffff;
89 } else {
90 coded_file_size = file_size - RSO_HEADER_SIZE;
91 }
92
93 /* update file size */
94 url_fseek(pb, 2, SEEK_SET);
95 put_be16(pb, coded_file_size);
96 url_fseek(pb, file_size, SEEK_SET);
97
98 put_flush_packet(pb);
99
100 return 0;
101 }
102
103 AVOutputFormat rso_muxer = {
104 .name = "rso",
105 .long_name = NULL_IF_CONFIG_SMALL("Lego Mindstorms RSO format"),
106 .extensions = "rso",
107 .priv_data_size = 0,
108 .audio_codec = CODEC_ID_PCM_U8,
109 .video_codec = CODEC_ID_NONE,
110 .write_header = rso_write_header,
111 .write_packet = rso_write_packet,
112 .write_trailer = rso_write_trailer,
113 .codec_tag = (const AVCodecTag* const []){ff_codec_rso_tags, 0},
114 };