FFmpeg: libavformat/mmf.c Source File

00001 /*
00002  * Yamaha SMAF format
00003  * Copyright (c) 2005 Vidar Madsen
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 #include "avformat.h"
00022 #include "avio_internal.h"
00023 #include "pcm.h"
00024 #include "riff.h"
00025 
00026 typedef struct {
00027     int64_t atrpos, atsqpos, awapos;
00028     int64_t data_size;
00029 } MMFContext;
00030 
00031 static const int mmf_rates[] = { 4000, 8000, 11025, 22050, 44100 };
00032 
00033 static int mmf_rate(int code)
00034 {
00035     if((code < 0) || (code > 4))
00036         return -1;
00037     return mmf_rates[code];
00038 }
00039 
00040 #if CONFIG_MMF_MUXER
00041 static int mmf_rate_code(int rate)
00042 {
00043     int i;
00044     for(i = 0; i < 5; i++)
00045         if(mmf_rates[i] == rate)
00046             return i;
00047     return -1;
00048 }
00049 
00050 /* Copy of end_tag() from avienc.c, but for big-endian chunk size */
00051 static void end_tag_be(AVIOContext *pb, int64_t start)
00052 {
00053     int64_t pos;
00054 
00055     pos = avio_tell(pb);
00056     avio_seek(pb, start - 4, SEEK_SET);
00057     avio_wb32(pb, (uint32_t)(pos - start));
00058     avio_seek(pb, pos, SEEK_SET);
00059 }
00060 
00061 static int mmf_write_header(AVFormatContext *s)
00062 {
00063     MMFContext *mmf = s->priv_data;
00064     AVIOContext *pb = s->pb;
00065     int64_t pos;
00066     int rate;
00067 
00068     rate = mmf_rate_code(s->streams[0]->codec->sample_rate);
00069     if(rate < 0) {
00070         av_log(s, AV_LOG_ERROR, "Unsupported sample rate %d\n", s->streams[0]->codec->sample_rate);
00071         return -1;
00072     }
00073 
00074     ffio_wfourcc(pb, "MMMD");
00075     avio_wb32(pb, 0);
00076     pos = ff_start_tag(pb, "CNTI");
00077     avio_w8(pb, 0); /* class */
00078     avio_w8(pb, 0); /* type */
00079     avio_w8(pb, 0); /* code type */
00080     avio_w8(pb, 0); /* status */
00081     avio_w8(pb, 0); /* counts */
00082     avio_write(pb, "VN:libavcodec,", sizeof("VN:libavcodec,") -1); /* metadata ("ST:songtitle,VN:version,...") */
00083     end_tag_be(pb, pos);
00084 
00085     avio_write(pb, "ATR\x00", 4);
00086     avio_wb32(pb, 0);
00087     mmf->atrpos = avio_tell(pb);
00088     avio_w8(pb, 0); /* format type */
00089     avio_w8(pb, 0); /* sequence type */
00090     avio_w8(pb, (0 << 7) | (1 << 4) | rate); /* (channel << 7) | (format << 4) | rate */
00091     avio_w8(pb, 0); /* wave base bit */
00092     avio_w8(pb, 2); /* time base d */
00093     avio_w8(pb, 2); /* time base g */
00094 
00095     ffio_wfourcc(pb, "Atsq");
00096     avio_wb32(pb, 16);
00097     mmf->atsqpos = avio_tell(pb);
00098     /* Will be filled on close */
00099     avio_write(pb, "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16);
00100 
00101     mmf->awapos = ff_start_tag(pb, "Awa\x01");
00102 
00103     av_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codec->sample_rate);
00104 
00105     avio_flush(pb);
00106 
00107     return 0;
00108 }
00109 
00110 static int mmf_write_packet(AVFormatContext *s, AVPacket *pkt)
00111 {
00112     AVIOContext *pb = s->pb;
00113     avio_write(pb, pkt->data, pkt->size);
00114     return 0;
00115 }
00116 
00117 /* Write a variable-length symbol */
00118 static void put_varlength(AVIOContext *pb, int val)
00119 {
00120     if(val < 128)
00121         avio_w8(pb, val);
00122     else {
00123         val -= 128;
00124         avio_w8(pb, 0x80 | val >> 7);
00125         avio_w8(pb, 0x7f & val);
00126     }
00127 }
00128 
00129 static int mmf_write_trailer(AVFormatContext *s)
00130 {
00131     AVIOContext *pb = s->pb;
00132     MMFContext *mmf = s->priv_data;
00133     int64_t pos, size;
00134     int gatetime;
00135 
00136     if (s->pb->seekable) {
00137         /* Fill in length fields */
00138         end_tag_be(pb, mmf->awapos);
00139         end_tag_be(pb, mmf->atrpos);
00140         end_tag_be(pb, 8);
00141 
00142         pos = avio_tell(pb);
00143         size = pos - mmf->awapos;
00144 
00145         /* Fill Atsq chunk */
00146         avio_seek(pb, mmf->atsqpos, SEEK_SET);
00147 
00148         /* "play wav" */
00149         avio_w8(pb, 0); /* start time */
00150         avio_w8(pb, 1); /* (channel << 6) | wavenum */
00151         gatetime = size * 500 / s->streams[0]->codec->sample_rate;
00152         put_varlength(pb, gatetime); /* duration */
00153 
00154         /* "nop" */
00155         put_varlength(pb, gatetime); /* start time */
00156         avio_write(pb, "\xff\x00", 2); /* nop */
00157 
00158         /* "end of sequence" */
00159         avio_write(pb, "\x00\x00\x00\x00", 4);
00160 
00161         avio_seek(pb, pos, SEEK_SET);
00162 
00163         avio_flush(pb);
00164     }
00165     return 0;
00166 }
00167 #endif /* CONFIG_MMF_MUXER */
00168 
00169 static int mmf_probe(AVProbeData *p)
00170 {
00171     /* check file header */
00172     if (p->buf[0] == 'M' && p->buf[1] == 'M' &&
00173         p->buf[2] == 'M' && p->buf[3] == 'D' &&
00174         p->buf[8] == 'C' && p->buf[9] == 'N' &&
00175         p->buf[10] == 'T' && p->buf[11] == 'I')
00176         return AVPROBE_SCORE_MAX;
00177     else
00178         return 0;
00179 }
00180 
00181 /* mmf input */
00182 static int mmf_read_header(AVFormatContext *s,
00183                            AVFormatParameters *ap)
00184 {
00185     MMFContext *mmf = s->priv_data;
00186     unsigned int tag;
00187     AVIOContext *pb = s->pb;
00188     AVStream *st;
00189     int64_t size;
00190     int rate, params;
00191 
00192     tag = avio_rl32(pb);
00193     if (tag != MKTAG('M', 'M', 'M', 'D'))
00194         return -1;
00195     avio_skip(pb, 4); /* file_size */
00196 
00197     /* Skip some unused chunks that may or may not be present */
00198     for(;; avio_skip(pb, size)) {
00199         tag = avio_rl32(pb);
00200         size = avio_rb32(pb);
00201         if(tag == MKTAG('C','N','T','I')) continue;
00202         if(tag == MKTAG('O','P','D','A')) continue;
00203         break;
00204     }
00205 
00206     /* Tag = "ATRx", where "x" = track number */
00207     if ((tag & 0xffffff) == MKTAG('M', 'T', 'R', 0)) {
00208         av_log(s, AV_LOG_ERROR, "MIDI like format found, unsupported\n");
00209         return -1;
00210     }
00211     if ((tag & 0xffffff) != MKTAG('A', 'T', 'R', 0)) {
00212         av_log(s, AV_LOG_ERROR, "Unsupported SMAF chunk %08x\n", tag);
00213         return -1;
00214     }
00215 
00216     avio_r8(pb); /* format type */
00217     avio_r8(pb); /* sequence type */
00218     params = avio_r8(pb); /* (channel << 7) | (format << 4) | rate */
00219     rate = mmf_rate(params & 0x0f);
00220     if(rate  < 0) {
00221         av_log(s, AV_LOG_ERROR, "Invalid sample rate\n");
00222         return -1;
00223     }
00224     avio_r8(pb); /* wave base bit */
00225     avio_r8(pb); /* time base d */
00226     avio_r8(pb); /* time base g */
00227 
00228     /* Skip some unused chunks that may or may not be present */
00229     for(;; avio_skip(pb, size)) {
00230         tag = avio_rl32(pb);
00231         size = avio_rb32(pb);
00232         if(tag == MKTAG('A','t','s','q')) continue;
00233         if(tag == MKTAG('A','s','p','I')) continue;
00234         break;
00235     }
00236 
00237     /* Make sure it's followed by an Awa chunk, aka wave data */
00238     if ((tag & 0xffffff) != MKTAG('A', 'w', 'a', 0)) {
00239         av_log(s, AV_LOG_ERROR, "Unexpected SMAF chunk %08x\n", tag);
00240         return -1;
00241     }
00242     mmf->data_size = size;
00243 
00244     st = av_new_stream(s, 0);
00245     if (!st)
00246         return AVERROR(ENOMEM);
00247 
00248     st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00249     st->codec->codec_id = CODEC_ID_ADPCM_YAMAHA;
00250     st->codec->sample_rate = rate;
00251     st->codec->channels = 1;
00252     st->codec->bits_per_coded_sample = 4;
00253     st->codec->bit_rate = st->codec->sample_rate * st->codec->bits_per_coded_sample;
00254 
00255     av_set_pts_info(st, 64, 1, st->codec->sample_rate);
00256 
00257     return 0;
00258 }
00259 
00260 #define MAX_SIZE 4096
00261 
00262 static int mmf_read_packet(AVFormatContext *s,
00263                            AVPacket *pkt)
00264 {
00265     MMFContext *mmf = s->priv_data;
00266     int ret, size;
00267 
00268     if (url_feof(s->pb))
00269         return AVERROR(EIO);
00270 
00271     size = MAX_SIZE;
00272     if(size > mmf->data_size)
00273         size = mmf->data_size;
00274 
00275     if(!size)
00276         return AVERROR(EIO);
00277 
00278     if (av_new_packet(pkt, size))
00279         return AVERROR(EIO);
00280     pkt->stream_index = 0;
00281 
00282     ret = avio_read(s->pb, pkt->data, pkt->size);
00283     if (ret < 0)
00284         av_free_packet(pkt);
00285 
00286     mmf->data_size -= ret;
00287 
00288     pkt->size = ret;
00289     return ret;
00290 }
00291 
00292 #if CONFIG_MMF_DEMUXER
00293 AVInputFormat ff_mmf_demuxer = {
00294     "mmf",
00295     NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
00296     sizeof(MMFContext),
00297     mmf_probe,
00298     mmf_read_header,
00299     mmf_read_packet,
00300     NULL,
00301     pcm_read_seek,
00302 };
00303 #endif
00304 #if CONFIG_MMF_MUXER
00305 AVOutputFormat ff_mmf_muxer = {
00306     "mmf",
00307     NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
00308     "application/vnd.smaf",
00309     "mmf",
00310     sizeof(MMFContext),
00311     CODEC_ID_ADPCM_YAMAHA,
00312     CODEC_ID_NONE,
00313     mmf_write_header,
00314     mmf_write_packet,
00315     mmf_write_trailer,
00316 };
00317 #endif