1/*
2 * WAV muxer and demuxer
3 * Copyright (c) 2001, 2002 Fabrice Bellard
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#include "avformat.h"
22#include "raw.h"
23#include "riff.h"
24
25typedef struct {
26    int64_t data;
27    int64_t data_end;
28    int64_t minpts;
29    int64_t maxpts;
30    int last_duration;
31} WAVContext;
32
33#if CONFIG_WAV_MUXER
34static int wav_write_header(AVFormatContext *s)
35{
36    WAVContext *wav = s->priv_data;
37    ByteIOContext *pb = s->pb;
38    int64_t fmt, fact;
39
40    put_tag(pb, "RIFF");
41    put_le32(pb, 0); /* file length */
42    put_tag(pb, "WAVE");
43
44    /* format header */
45    fmt = start_tag(pb, "fmt ");
46    if (put_wav_header(pb, s->streams[0]->codec) < 0) {
47        av_log(s, AV_LOG_ERROR, "%s codec not supported in WAVE format\n",
48               s->streams[0]->codec->codec ? s->streams[0]->codec->codec->name : "NONE");
49        av_free(wav);
50        return -1;
51    }
52    end_tag(pb, fmt);
53
54    if(s->streams[0]->codec->codec_tag != 0x01 /* hence for all other than PCM */
55       && !url_is_streamed(s->pb)) {
56        fact = start_tag(pb, "fact");
57        put_le32(pb, 0);
58        end_tag(pb, fact);
59    }
60
61    av_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codec->sample_rate);
62    wav->maxpts = wav->last_duration = 0;
63    wav->minpts = INT64_MAX;
64
65    /* data header */
66    wav->data = start_tag(pb, "data");
67
68    put_flush_packet(pb);
69
70    return 0;
71}
72
73static int wav_write_packet(AVFormatContext *s, AVPacket *pkt)
74{
75    ByteIOContext *pb = s->pb;
76    WAVContext *wav = s->priv_data;
77    put_buffer(pb, pkt->data, pkt->size);
78    if(pkt->pts != AV_NOPTS_VALUE) {
79        wav->minpts = FFMIN(wav->minpts, pkt->pts);
80        wav->maxpts = FFMAX(wav->maxpts, pkt->pts);
81        wav->last_duration = pkt->duration;
82    } else
83        av_log(s, AV_LOG_ERROR, "wav_write_packet: NOPTS\n");
84    return 0;
85}
86
87static int wav_write_trailer(AVFormatContext *s)
88{
89    ByteIOContext *pb = s->pb;
90    WAVContext *wav = s->priv_data;
91    int64_t file_size;
92
93    if (!url_is_streamed(s->pb)) {
94        end_tag(pb, wav->data);
95
96        /* update file size */
97        file_size = url_ftell(pb);
98        url_fseek(pb, 4, SEEK_SET);
99        put_le32(pb, (uint32_t)(file_size - 8));
100        url_fseek(pb, file_size, SEEK_SET);
101
102        put_flush_packet(pb);
103
104        if(s->streams[0]->codec->codec_tag != 0x01) {
105            /* Update num_samps in fact chunk */
106            int number_of_samples;
107            number_of_samples = av_rescale(wav->maxpts - wav->minpts + wav->last_duration,
108                                           s->streams[0]->codec->sample_rate * (int64_t)s->streams[0]->time_base.num,
109                                           s->streams[0]->time_base.den);
110            url_fseek(pb, wav->data-12, SEEK_SET);
111            put_le32(pb, number_of_samples);
112            url_fseek(pb, file_size, SEEK_SET);
113            put_flush_packet(pb);
114        }
115    }
116    return 0;
117}
118#endif /* CONFIG_WAV_MUXER */
119
120/* return the size of the found tag */
121/* XXX: > 2GB ? */
122static int find_tag(ByteIOContext *pb, uint32_t tag1)
123{
124    unsigned int tag;
125    int size;
126
127    for(;;) {
128        if (url_feof(pb))
129            return -1;
130        tag = get_le32(pb);
131        size = get_le32(pb);
132        if (tag == tag1)
133            break;
134        url_fseek(pb, size, SEEK_CUR);
135    }
136    if (size < 0)
137        size = 0x7fffffff;
138    return size;
139}
140
141static int wav_probe(AVProbeData *p)
142{
143    /* check file header */
144    if (p->buf_size <= 32)
145        return 0;
146    if (p->buf[0] == 'R' && p->buf[1] == 'I' &&
147        p->buf[2] == 'F' && p->buf[3] == 'F' &&
148        p->buf[8] == 'W' && p->buf[9] == 'A' &&
149        p->buf[10] == 'V' && p->buf[11] == 'E')
150        /*
151          Since ACT demuxer has standard WAV header at top of it's own,
152          returning score is decreased to avoid probe conflict
153          between ACT and WAV.
154        */
155        return AVPROBE_SCORE_MAX - 1;
156    else
157        return 0;
158}
159
160/* wav input */
161static int wav_read_header(AVFormatContext *s,
162                           AVFormatParameters *ap)
163{
164    int size;
165    unsigned int tag;
166    ByteIOContext *pb = s->pb;
167    AVStream *st;
168    WAVContext *wav = s->priv_data;
169
170    /* check RIFF header */
171    tag = get_le32(pb);
172
173    if (tag != MKTAG('R', 'I', 'F', 'F'))
174        return -1;
175    get_le32(pb); /* file size */
176    tag = get_le32(pb);
177    if (tag != MKTAG('W', 'A', 'V', 'E'))
178        return -1;
179
180    /* parse fmt header */
181    size = find_tag(pb, MKTAG('f', 'm', 't', ' '));
182    if (size < 0)
183        return -1;
184    st = av_new_stream(s, 0);
185    if (!st)
186        return AVERROR(ENOMEM);
187
188    get_wav_header(pb, st->codec, size);
189    st->need_parsing = AVSTREAM_PARSE_FULL;
190
191    av_set_pts_info(st, 64, 1, st->codec->sample_rate);
192
193    size = find_tag(pb, MKTAG('d', 'a', 't', 'a'));
194    if (size < 0)
195        return -1;
196    wav->data_end= url_ftell(pb) + size;
197    return 0;
198}
199
200#define MAX_SIZE 4096
201
202static int wav_read_packet(AVFormatContext *s,
203                           AVPacket *pkt)
204{
205    int ret, size, left;
206    AVStream *st;
207    WAVContext *wav = s->priv_data;
208
209    if (url_feof(s->pb))
210        return AVERROR(EIO);
211    st = s->streams[0];
212
213    left= wav->data_end - url_ftell(s->pb);
214    if(left <= 0){
215        left = find_tag(s->pb, MKTAG('d', 'a', 't', 'a'));
216        if (left < 0) {
217            return AVERROR(EIO);
218        }
219        wav->data_end= url_ftell(s->pb) + left;
220    }
221
222    size = MAX_SIZE;
223    if (st->codec->block_align > 1) {
224        if (size < st->codec->block_align)
225            size = st->codec->block_align;
226        size = (size / st->codec->block_align) * st->codec->block_align;
227    }
228    size= FFMIN(size, left);
229    ret= av_get_packet(s->pb, pkt, size);
230    if (ret <= 0)
231        return AVERROR(EIO);
232    pkt->stream_index = 0;
233
234    /* note: we need to modify the packet size here to handle the last
235       packet */
236    pkt->size = ret;
237    return ret;
238}
239
240static int wav_read_seek(AVFormatContext *s,
241                         int stream_index, int64_t timestamp, int flags)
242{
243    AVStream *st;
244
245    st = s->streams[0];
246    switch(st->codec->codec_id) {
247    case CODEC_ID_MP2:
248    case CODEC_ID_MP3:
249    case CODEC_ID_AC3:
250    case CODEC_ID_DTS:
251        /* use generic seeking with dynamically generated indexes */
252        return -1;
253    default:
254        break;
255    }
256    return pcm_read_seek(s, stream_index, timestamp, flags);
257}
258
259#if CONFIG_WAV_DEMUXER
260AVInputFormat wav_demuxer = {
261    "wav",
262    NULL_IF_CONFIG_SMALL("WAV format"),
263    sizeof(WAVContext),
264    wav_probe,
265    wav_read_header,
266    wav_read_packet,
267    NULL,
268    wav_read_seek,
269    .flags= AVFMT_GENERIC_INDEX,
270    .codec_tag= (const AVCodecTag* const []){codec_wav_tags, 0},
271};
272#endif
273#if CONFIG_WAV_MUXER
274AVOutputFormat wav_muxer = {
275    "wav",
276    NULL_IF_CONFIG_SMALL("WAV format"),
277    "audio/x-wav",
278    "wav",
279    sizeof(WAVContext),
280    CODEC_ID_PCM_S16LE,
281    CODEC_ID_NONE,
282    wav_write_header,
283    wav_write_packet,
284    wav_write_trailer,
285    .codec_tag= (const AVCodecTag* const []){codec_wav_tags, 0},
286};
287#endif
288