1/*
2 * Yamaha SMAF format
3 * Copyright (c) 2005 Vidar Madsen
4 *
5 * This file is part of Libav.
6 *
7 * Libav 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 * Libav 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 Libav; 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 "internal.h"
23#include "avio_internal.h"
24#include "pcm.h"
25#include "riff.h"
26
27typedef struct {
28    int64_t atrpos, atsqpos, awapos;
29    int64_t data_size;
30} MMFContext;
31
32static const int mmf_rates[] = { 4000, 8000, 11025, 22050, 44100 };
33
34static int mmf_rate(int code)
35{
36    if((code < 0) || (code > 4))
37        return -1;
38    return mmf_rates[code];
39}
40
41#if CONFIG_MMF_MUXER
42static int mmf_rate_code(int rate)
43{
44    int i;
45    for(i = 0; i < 5; i++)
46        if(mmf_rates[i] == rate)
47            return i;
48    return -1;
49}
50
51/* Copy of end_tag() from avienc.c, but for big-endian chunk size */
52static void end_tag_be(AVIOContext *pb, int64_t start)
53{
54    int64_t pos;
55
56    pos = avio_tell(pb);
57    avio_seek(pb, start - 4, SEEK_SET);
58    avio_wb32(pb, (uint32_t)(pos - start));
59    avio_seek(pb, pos, SEEK_SET);
60}
61
62static int mmf_write_header(AVFormatContext *s)
63{
64    MMFContext *mmf = s->priv_data;
65    AVIOContext *pb = s->pb;
66    int64_t pos;
67    int rate;
68
69    rate = mmf_rate_code(s->streams[0]->codec->sample_rate);
70    if(rate < 0) {
71        av_log(s, AV_LOG_ERROR, "Unsupported sample rate %d\n", s->streams[0]->codec->sample_rate);
72        return -1;
73    }
74
75    ffio_wfourcc(pb, "MMMD");
76    avio_wb32(pb, 0);
77    pos = ff_start_tag(pb, "CNTI");
78    avio_w8(pb, 0); /* class */
79    avio_w8(pb, 0); /* type */
80    avio_w8(pb, 0); /* code type */
81    avio_w8(pb, 0); /* status */
82    avio_w8(pb, 0); /* counts */
83    avio_write(pb, "VN:libavcodec,", sizeof("VN:libavcodec,") -1); /* metadata ("ST:songtitle,VN:version,...") */
84    end_tag_be(pb, pos);
85
86    avio_write(pb, "ATR\x00", 4);
87    avio_wb32(pb, 0);
88    mmf->atrpos = avio_tell(pb);
89    avio_w8(pb, 0); /* format type */
90    avio_w8(pb, 0); /* sequence type */
91    avio_w8(pb, (0 << 7) | (1 << 4) | rate); /* (channel << 7) | (format << 4) | rate */
92    avio_w8(pb, 0); /* wave base bit */
93    avio_w8(pb, 2); /* time base d */
94    avio_w8(pb, 2); /* time base g */
95
96    ffio_wfourcc(pb, "Atsq");
97    avio_wb32(pb, 16);
98    mmf->atsqpos = avio_tell(pb);
99    /* Will be filled on close */
100    avio_write(pb, "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16);
101
102    mmf->awapos = ff_start_tag(pb, "Awa\x01");
103
104    avpriv_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codec->sample_rate);
105
106    avio_flush(pb);
107
108    return 0;
109}
110
111static int mmf_write_packet(AVFormatContext *s, AVPacket *pkt)
112{
113    AVIOContext *pb = s->pb;
114    avio_write(pb, pkt->data, pkt->size);
115    return 0;
116}
117
118/* Write a variable-length symbol */
119static void put_varlength(AVIOContext *pb, int val)
120{
121    if(val < 128)
122        avio_w8(pb, val);
123    else {
124        val -= 128;
125        avio_w8(pb, 0x80 | val >> 7);
126        avio_w8(pb, 0x7f & val);
127    }
128}
129
130static int mmf_write_trailer(AVFormatContext *s)
131{
132    AVIOContext *pb = s->pb;
133    MMFContext *mmf = s->priv_data;
134    int64_t pos, size;
135    int gatetime;
136
137    if (s->pb->seekable) {
138        /* Fill in length fields */
139        end_tag_be(pb, mmf->awapos);
140        end_tag_be(pb, mmf->atrpos);
141        end_tag_be(pb, 8);
142
143        pos = avio_tell(pb);
144        size = pos - mmf->awapos;
145
146        /* Fill Atsq chunk */
147        avio_seek(pb, mmf->atsqpos, SEEK_SET);
148
149        /* "play wav" */
150        avio_w8(pb, 0); /* start time */
151        avio_w8(pb, 1); /* (channel << 6) | wavenum */
152        gatetime = size * 500 / s->streams[0]->codec->sample_rate;
153        put_varlength(pb, gatetime); /* duration */
154
155        /* "nop" */
156        put_varlength(pb, gatetime); /* start time */
157        avio_write(pb, "\xff\x00", 2); /* nop */
158
159        /* "end of sequence" */
160        avio_write(pb, "\x00\x00\x00\x00", 4);
161
162        avio_seek(pb, pos, SEEK_SET);
163
164        avio_flush(pb);
165    }
166    return 0;
167}
168#endif /* CONFIG_MMF_MUXER */
169
170static int mmf_probe(AVProbeData *p)
171{
172    /* check file header */
173    if (p->buf[0] == 'M' && p->buf[1] == 'M' &&
174        p->buf[2] == 'M' && p->buf[3] == 'D' &&
175        p->buf[8] == 'C' && p->buf[9] == 'N' &&
176        p->buf[10] == 'T' && p->buf[11] == 'I')
177        return AVPROBE_SCORE_MAX;
178    else
179        return 0;
180}
181
182/* mmf input */
183static int mmf_read_header(AVFormatContext *s,
184                           AVFormatParameters *ap)
185{
186    MMFContext *mmf = s->priv_data;
187    unsigned int tag;
188    AVIOContext *pb = s->pb;
189    AVStream *st;
190    int64_t size;
191    int rate, params;
192
193    tag = avio_rl32(pb);
194    if (tag != MKTAG('M', 'M', 'M', 'D'))
195        return -1;
196    avio_skip(pb, 4); /* file_size */
197
198    /* Skip some unused chunks that may or may not be present */
199    for(;; avio_skip(pb, size)) {
200        tag = avio_rl32(pb);
201        size = avio_rb32(pb);
202        if(tag == MKTAG('C','N','T','I')) continue;
203        if(tag == MKTAG('O','P','D','A')) continue;
204        break;
205    }
206
207    /* Tag = "ATRx", where "x" = track number */
208    if ((tag & 0xffffff) == MKTAG('M', 'T', 'R', 0)) {
209        av_log(s, AV_LOG_ERROR, "MIDI like format found, unsupported\n");
210        return -1;
211    }
212    if ((tag & 0xffffff) != MKTAG('A', 'T', 'R', 0)) {
213        av_log(s, AV_LOG_ERROR, "Unsupported SMAF chunk %08x\n", tag);
214        return -1;
215    }
216
217    avio_r8(pb); /* format type */
218    avio_r8(pb); /* sequence type */
219    params = avio_r8(pb); /* (channel << 7) | (format << 4) | rate */
220    rate = mmf_rate(params & 0x0f);
221    if(rate  < 0) {
222        av_log(s, AV_LOG_ERROR, "Invalid sample rate\n");
223        return -1;
224    }
225    avio_r8(pb); /* wave base bit */
226    avio_r8(pb); /* time base d */
227    avio_r8(pb); /* time base g */
228
229    /* Skip some unused chunks that may or may not be present */
230    for(;; avio_skip(pb, size)) {
231        tag = avio_rl32(pb);
232        size = avio_rb32(pb);
233        if(tag == MKTAG('A','t','s','q')) continue;
234        if(tag == MKTAG('A','s','p','I')) continue;
235        break;
236    }
237
238    /* Make sure it's followed by an Awa chunk, aka wave data */
239    if ((tag & 0xffffff) != MKTAG('A', 'w', 'a', 0)) {
240        av_log(s, AV_LOG_ERROR, "Unexpected SMAF chunk %08x\n", tag);
241        return -1;
242    }
243    mmf->data_size = size;
244
245    st = avformat_new_stream(s, NULL);
246    if (!st)
247        return AVERROR(ENOMEM);
248
249    st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
250    st->codec->codec_id = CODEC_ID_ADPCM_YAMAHA;
251    st->codec->sample_rate = rate;
252    st->codec->channels = 1;
253    st->codec->bits_per_coded_sample = 4;
254    st->codec->bit_rate = st->codec->sample_rate * st->codec->bits_per_coded_sample;
255
256    avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
257
258    return 0;
259}
260
261#define MAX_SIZE 4096
262
263static int mmf_read_packet(AVFormatContext *s,
264                           AVPacket *pkt)
265{
266    MMFContext *mmf = s->priv_data;
267    int ret, size;
268
269    if (s->pb->eof_reached)
270        return AVERROR(EIO);
271
272    size = MAX_SIZE;
273    if(size > mmf->data_size)
274        size = mmf->data_size;
275
276    if(!size)
277        return AVERROR(EIO);
278
279    if (av_new_packet(pkt, size))
280        return AVERROR(EIO);
281    pkt->stream_index = 0;
282
283    ret = avio_read(s->pb, pkt->data, pkt->size);
284    if (ret < 0)
285        av_free_packet(pkt);
286
287    mmf->data_size -= ret;
288
289    pkt->size = ret;
290    return ret;
291}
292
293#if CONFIG_MMF_DEMUXER
294AVInputFormat ff_mmf_demuxer = {
295    .name           = "mmf",
296    .long_name      = NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
297    .priv_data_size = sizeof(MMFContext),
298    .read_probe     = mmf_probe,
299    .read_header    = mmf_read_header,
300    .read_packet    = mmf_read_packet,
301    .read_seek      = pcm_read_seek,
302};
303#endif
304#if CONFIG_MMF_MUXER
305AVOutputFormat ff_mmf_muxer = {
306    .name              = "mmf",
307    .long_name         = NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
308    .mime_type         = "application/vnd.smaf",
309    .extensions        = "mmf",
310    .priv_data_size    = sizeof(MMFContext),
311    .audio_codec       = CODEC_ID_ADPCM_YAMAHA,
312    .video_codec       = CODEC_ID_NONE,
313    .write_header      = mmf_write_header,
314    .write_packet      = mmf_write_packet,
315    .write_trailer     = mmf_write_trailer,
316};
317#endif
318