Musepack SV8 demuxer and decoder

Originally committed as revision 10938 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 244 insertions, 0 deletions

diff --git a/libavformat/mpc8.c b/libavformat/mpc8.c
new file mode 100644
index 0000000000..b6840b00d6
--- /dev/null
+++ b/libavformat/mpc8.c
@@ -0,0 +1,244 @@
+/*
+ * Musepack SV8 demuxer
+ * Copyright (c) 2007 Konstantin Shishkov
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#include "avformat.h"
+#include "bitstream.h"
+#include "unary.h"
+
+/// Two-byte MPC tag
+#define MKMPCTAG(a, b) (a | (b << 8))
+
+#define TAG_MPCK MKTAG('M','P','C','K')
+
+/// Reserved MPC tags
+enum MPCPacketTags{
+    TAG_STREAMHDR   = MKMPCTAG('S','H'),
+    TAG_STREAMEND   = MKMPCTAG('S','E'),
+
+    TAG_AUDIOPACKET = MKMPCTAG('A','P'),
+
+    TAG_SEEKTBLOFF  = MKMPCTAG('S','O'),
+    TAG_SEEKTABLE   = MKMPCTAG('S','T'),
+
+    TAG_REPLAYGAIN  = MKMPCTAG('R','G'),
+    TAG_ENCINFO     = MKMPCTAG('E','I'),
+};
+
+static const int mpc8_rate[8] = { 44100, 48000, 37800, 32000, -1, -1, -1, -1 };
+
+typedef struct {
+    int ver;
+    int frame;
+    int64_t header_pos;
+    int64_t samples;
+} MPCContext;
+
+static int mpc8_probe(AVProbeData *p)
+{
+    if (AV_RL32(p->buf) == TAG_MPCK)
+        return AVPROBE_SCORE_MAX;
+    return 0;
+}
+
+static inline int64_t gb_get_v(GetBitContext *gb)
+{
+    int64_t v = 0;
+    int bits = 0;
+    while(get_bits1(gb) && bits < 64-7){
+        v <<= 7;
+        v |= get_bits(gb, 7);
+        bits += 7;
+    }
+    v <<= 7;
+    v |= get_bits(gb, 7);
+
+    return v;
+}
+
+static void mpc8_get_chunk_header(ByteIOContext *pb, int *tag, int64_t *size)
+{
+    int64_t pos;
+    pos = url_ftell(pb);
+    *tag = get_le16(pb);
+    *size = ff_get_v(pb);
+    *size -= url_ftell(pb) - pos;
+}
+
+static void mpc8_parse_seektable(AVFormatContext *s, int64_t off)
+{
+    MPCContext *c = s->priv_data;
+    int tag;
+    int64_t size, pos, ppos[2];
+    uint8_t *buf;
+    int i, t, seekd;
+    GetBitContext gb;
+
+    url_fseek(&s->pb, off, SEEK_SET);
+    mpc8_get_chunk_header(&s->pb, &tag, &size);
+    if(tag != TAG_SEEKTABLE){
+        av_log(s, AV_LOG_ERROR, "No seek table at given position\n");
+        return;
+    }
+    if(!(buf = av_malloc(size)))
+        return;
+    get_buffer(&s->pb, buf, size);
+    init_get_bits(&gb, buf, size * 8);
+    size = gb_get_v(&gb);
+    if(size > UINT_MAX/4 || size > c->samples/1152){
+        av_log(s, AV_LOG_ERROR, "Seek table is too big\n");
+        return;
+    }
+    seekd = get_bits(&gb, 4);
+    for(i = 0; i < 2; i++){
+        pos = gb_get_v(&gb) + c->header_pos;
+        ppos[1 - i] = pos;
+        av_add_index_entry(s->streams[0], pos, i, 0, 0, AVINDEX_KEYFRAME);
+    }
+    for(; i < size; i++){
+        t = get_unary(&gb, 1, 33) << 12;
+        t += get_bits(&gb, 12);
+        if(t & 1)
+            t = -(t & ~1);
+        pos = (t >> 1) + ppos[0]*2 - ppos[1];
+        av_add_index_entry(s->streams[0], pos, i << seekd, 0, 0, AVINDEX_KEYFRAME);
+        ppos[1] = ppos[0];
+        ppos[0] = pos;
+    }
+    av_free(buf);
+}
+
+static void mpc8_handle_chunk(AVFormatContext *s, int tag, int64_t chunk_pos, int64_t size)
+{
+    ByteIOContext *pb = &s->pb;
+    int64_t pos, off;
+
+    switch(tag){
+    case TAG_SEEKTBLOFF:
+        pos = url_ftell(pb) + size;
+        off = ff_get_v(pb);
+        mpc8_parse_seektable(s, chunk_pos + off);
+        url_fseek(pb, pos, SEEK_SET);
+        break;
+    default:
+        url_fskip(pb, size);
+    }
+}
+
+static int mpc8_read_header(AVFormatContext *s, AVFormatParameters *ap)
+{
+    MPCContext *c = s->priv_data;
+    ByteIOContext *pb = &s->pb;
+    AVStream *st;
+    int tag = 0;
+    int64_t size, pos;
+
+    c->header_pos = url_ftell(pb);
+    if(get_le32(pb) != TAG_MPCK){
+        av_log(s, AV_LOG_ERROR, "Not a Musepack8 file\n");
+        return -1;
+    }
+
+    while(!url_feof(pb)){
+        pos = url_ftell(pb);
+        mpc8_get_chunk_header(pb, &tag, &size);
+        if(tag == TAG_STREAMHDR)
+            break;
+        mpc8_handle_chunk(s, tag, pos, size);
+    }
+    if(tag != TAG_STREAMHDR){
+        av_log(s, AV_LOG_ERROR, "Stream header not found\n");
+        return -1;
+    }
+    pos = url_ftell(pb);
+    url_fskip(pb, 4); //CRC
+    c->ver = get_byte(pb);
+    if(c->ver != 8){
+        av_log(s, AV_LOG_ERROR, "Unknown stream version %d\n", c->ver);
+        return -1;
+    }
+    c->samples = ff_get_v(pb);
+    ff_get_v(pb); //silence samples at the beginning
+
+    st = av_new_stream(s, 0);
+    if (!st)
+        return AVERROR(ENOMEM);
+    st->codec->codec_type = CODEC_TYPE_AUDIO;
+    st->codec->codec_id = CODEC_ID_MUSEPACK8;
+    st->codec->bits_per_sample = 16;
+
+    st->codec->extradata_size = 2;
+    st->codec->extradata = av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
+    get_buffer(pb, st->codec->extradata, st->codec->extradata_size);
+
+    st->codec->channels = (st->codec->extradata[1] >> 4) + 1;
+    st->codec->sample_rate = mpc8_rate[st->codec->extradata[0] >> 5];
+    av_set_pts_info(st, 32, 1152  << (st->codec->extradata[1]&3)*2, st->codec->sample_rate);
+    st->duration = c->samples / (1152 << (st->codec->extradata[1]&3)*2);
+    size -= url_ftell(pb) - pos;
+
+    return 0;
+}
+
+static int mpc8_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    MPCContext *c = s->priv_data;
+    int tag;
+    int64_t pos, size;
+
+    while(!url_feof(&s->pb)){
+        pos = url_ftell(&s->pb);
+        mpc8_get_chunk_header(&s->pb, &tag, &size);
+        if(tag == TAG_AUDIOPACKET){
+            if(av_get_packet(&s->pb, pkt, size) < 0)
+                return AVERROR(ENOMEM);
+            pkt->stream_index = 0;
+            pkt->pts = c->frame;
+            return 0;
+        }
+        if(tag == TAG_STREAMEND)
+            return AVERROR(EIO);
+        mpc8_handle_chunk(s, tag, pos, size);
+    }
+    return 0;
+}
+
+static int mpc8_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
+{
+    AVStream *st = s->streams[stream_index];
+    MPCContext *c = s->priv_data;
+    int index = av_index_search_timestamp(st, timestamp, flags);
+
+    if(index < 0) return -1;
+    url_fseek(&s->pb, st->index_entries[index].pos, SEEK_SET);
+    c->frame = st->index_entries[index].timestamp;
+    return 0;
+}
+
+
+AVInputFormat mpc8_demuxer = {
+    "mpc8",
+    "musepack8",
+    sizeof(MPCContext),
+    mpc8_probe,
+    mpc8_read_header,
+    mpc8_read_packet,
+    NULL,
+    mpc8_read_seek,
+};