1/*
2 * Yamaha SMAF format
3 * Copyright (c) 2005 Vidar Madsen
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 atrpos, atsqpos, awapos;
27    int64_t data_size;
28} MMFContext;
29
30static const int mmf_rates[] = { 4000, 8000, 11025, 22050, 44100 };
31
32static int mmf_rate(int code)
33{
34    if((code < 0) || (code > 4))
35        return -1;
36    return mmf_rates[code];
37}
38
39#if CONFIG_MMF_MUXER
40static int mmf_rate_code(int rate)
41{
42    int i;
43    for(i = 0; i < 5; i++)
44        if(mmf_rates[i] == rate)
45            return i;
46    return -1;
47}
48
49/* Copy of end_tag() from avienc.c, but for big-endian chunk size */
50static void end_tag_be(ByteIOContext *pb, int64_t start)
51{
52    int64_t pos;
53
54    pos = url_ftell(pb);
55    url_fseek(pb, start - 4, SEEK_SET);
56    put_be32(pb, (uint32_t)(pos - start));
57    url_fseek(pb, pos, SEEK_SET);
58}
59
60static int mmf_write_header(AVFormatContext *s)
61{
62    MMFContext *mmf = s->priv_data;
63    ByteIOContext *pb = s->pb;
64    int64_t pos;
65    int rate;
66
67    rate = mmf_rate_code(s->streams[0]->codec->sample_rate);
68    if(rate < 0) {
69        av_log(s, AV_LOG_ERROR, "Unsupported sample rate %d\n", s->streams[0]->codec->sample_rate);
70        return -1;
71    }
72
73    put_tag(pb, "MMMD");
74    put_be32(pb, 0);
75    pos = start_tag(pb, "CNTI");
76    put_byte(pb, 0); /* class */
77    put_byte(pb, 0); /* type */
78    put_byte(pb, 0); /* code type */
79    put_byte(pb, 0); /* status */
80    put_byte(pb, 0); /* counts */
81    put_tag(pb, "VN:libavcodec,"); /* metadata ("ST:songtitle,VN:version,...") */
82    end_tag_be(pb, pos);
83
84    put_buffer(pb, "ATR\x00", 4);
85    put_be32(pb, 0);
86    mmf->atrpos = url_ftell(pb);
87    put_byte(pb, 0); /* format type */
88    put_byte(pb, 0); /* sequence type */
89    put_byte(pb, (0 << 7) | (1 << 4) | rate); /* (channel << 7) | (format << 4) | rate */
90    put_byte(pb, 0); /* wave base bit */
91    put_byte(pb, 2); /* time base d */
92    put_byte(pb, 2); /* time base g */
93
94    put_tag(pb, "Atsq");
95    put_be32(pb, 16);
96    mmf->atsqpos = url_ftell(pb);
97    /* Will be filled on close */
98    put_buffer(pb, "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16);
99
100    mmf->awapos = start_tag(pb, "Awa\x01");
101
102    av_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codec->sample_rate);
103
104    put_flush_packet(pb);
105
106    return 0;
107}
108
109static int mmf_write_packet(AVFormatContext *s, AVPacket *pkt)
110{
111    ByteIOContext *pb = s->pb;
112    put_buffer(pb, pkt->data, pkt->size);
113    return 0;
114}
115
116/* Write a variable-length symbol */
117static void put_varlength(ByteIOContext *pb, int val)
118{
119    if(val < 128)
120        put_byte(pb, val);
121    else {
122        val -= 128;
123        put_byte(pb, 0x80 | val >> 7);
124        put_byte(pb, 0x7f & val);
125    }
126}
127
128static int mmf_write_trailer(AVFormatContext *s)
129{
130    ByteIOContext *pb = s->pb;
131    MMFContext *mmf = s->priv_data;
132    int64_t pos, size;
133    int gatetime;
134
135    if (!url_is_streamed(s->pb)) {
136        /* Fill in length fields */
137        end_tag_be(pb, mmf->awapos);
138        end_tag_be(pb, mmf->atrpos);
139        end_tag_be(pb, 8);
140
141        pos = url_ftell(pb);
142        size = pos - mmf->awapos;
143
144        /* Fill Atsq chunk */
145        url_fseek(pb, mmf->atsqpos, SEEK_SET);
146
147        /* "play wav" */
148        put_byte(pb, 0); /* start time */
149        put_byte(pb, 1); /* (channel << 6) | wavenum */
150        gatetime = size * 500 / s->streams[0]->codec->sample_rate;
151        put_varlength(pb, gatetime); /* duration */
152
153        /* "nop" */
154        put_varlength(pb, gatetime); /* start time */
155        put_buffer(pb, "\xff\x00", 2); /* nop */
156
157        /* "end of sequence" */
158        put_buffer(pb, "\x00\x00\x00\x00", 4);
159
160        url_fseek(pb, pos, SEEK_SET);
161
162        put_flush_packet(pb);
163    }
164    return 0;
165}
166#endif /* CONFIG_MMF_MUXER */
167
168static int mmf_probe(AVProbeData *p)
169{
170    /* check file header */
171    if (p->buf[0] == 'M' && p->buf[1] == 'M' &&
172        p->buf[2] == 'M' && p->buf[3] == 'D' &&
173        p->buf[8] == 'C' && p->buf[9] == 'N' &&
174        p->buf[10] == 'T' && p->buf[11] == 'I')
175        return AVPROBE_SCORE_MAX;
176    else
177        return 0;
178}
179
180/* mmf input */
181static int mmf_read_header(AVFormatContext *s,
182                           AVFormatParameters *ap)
183{
184    MMFContext *mmf = s->priv_data;
185    unsigned int tag;
186    ByteIOContext *pb = s->pb;
187    AVStream *st;
188    int64_t file_size, size;
189    int rate, params;
190
191    tag = get_le32(pb);
192    if (tag != MKTAG('M', 'M', 'M', 'D'))
193        return -1;
194    file_size = get_be32(pb);
195
196    /* Skip some unused chunks that may or may not be present */
197    for(;; url_fseek(pb, size, SEEK_CUR)) {
198        tag = get_le32(pb);
199        size = get_be32(pb);
200        if(tag == MKTAG('C','N','T','I')) continue;
201        if(tag == MKTAG('O','P','D','A')) continue;
202        break;
203    }
204
205    /* Tag = "ATRx", where "x" = track number */
206    if ((tag & 0xffffff) == MKTAG('M', 'T', 'R', 0)) {
207        av_log(s, AV_LOG_ERROR, "MIDI like format found, unsupported\n");
208        return -1;
209    }
210    if ((tag & 0xffffff) != MKTAG('A', 'T', 'R', 0)) {
211        av_log(s, AV_LOG_ERROR, "Unsupported SMAF chunk %08x\n", tag);
212        return -1;
213    }
214
215    get_byte(pb); /* format type */
216    get_byte(pb); /* sequence type */
217    params = get_byte(pb); /* (channel << 7) | (format << 4) | rate */
218    rate = mmf_rate(params & 0x0f);
219    if(rate  < 0) {
220        av_log(s, AV_LOG_ERROR, "Invalid sample rate\n");
221        return -1;
222    }
223    get_byte(pb); /* wave base bit */
224    get_byte(pb); /* time base d */
225    get_byte(pb); /* time base g */
226
227    /* Skip some unused chunks that may or may not be present */
228    for(;; url_fseek(pb, size, SEEK_CUR)) {
229        tag = get_le32(pb);
230        size = get_be32(pb);
231        if(tag == MKTAG('A','t','s','q')) continue;
232        if(tag == MKTAG('A','s','p','I')) continue;
233        break;
234    }
235
236    /* Make sure it's followed by an Awa chunk, aka wave data */
237    if ((tag & 0xffffff) != MKTAG('A', 'w', 'a', 0)) {
238        av_log(s, AV_LOG_ERROR, "Unexpected SMAF chunk %08x\n", tag);
239        return -1;
240    }
241    mmf->data_size = size;
242
243    st = av_new_stream(s, 0);
244    if (!st)
245        return AVERROR(ENOMEM);
246
247    st->codec->codec_type = CODEC_TYPE_AUDIO;
248    st->codec->codec_id = CODEC_ID_ADPCM_YAMAHA;
249    st->codec->sample_rate = rate;
250    st->codec->channels = 1;
251    st->codec->bits_per_coded_sample = 4;
252    st->codec->bit_rate = st->codec->sample_rate * st->codec->bits_per_coded_sample;
253
254    av_set_pts_info(st, 64, 1, st->codec->sample_rate);
255
256    return 0;
257}
258
259#define MAX_SIZE 4096
260
261static int mmf_read_packet(AVFormatContext *s,
262                           AVPacket *pkt)
263{
264    MMFContext *mmf = s->priv_data;
265    AVStream *st;
266    int ret, size;
267
268    if (url_feof(s->pb))
269        return AVERROR(EIO);
270    st = s->streams[0];
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 = get_buffer(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 mmf_demuxer = {
295    "mmf",
296    NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
297    sizeof(MMFContext),
298    mmf_probe,
299    mmf_read_header,
300    mmf_read_packet,
301    NULL,
302    pcm_read_seek,
303};
304#endif
305#if CONFIG_MMF_MUXER
306AVOutputFormat mmf_muxer = {
307    "mmf",
308    NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
309    "application/vnd.smaf",
310    "mmf",
311    sizeof(MMFContext),
312    CODEC_ID_ADPCM_YAMAHA,
313    CODEC_ID_NONE,
314    mmf_write_header,
315    mmf_write_packet,
316    mmf_write_trailer,
317};
318#endif
319