Musepack SV7 decoding support

Originally committed as revision 7375 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 182 insertions, 0 deletions

diff --git a/libavformat/mpc.c b/libavformat/mpc.c
new file mode 100644
index 0000000000..abc7617695
--- /dev/null
+++ b/libavformat/mpc.c
@@ -0,0 +1,182 @@
+/*
+ * Musepack demuxer
+ * Copyright (c) 2006 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 St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+#include "avformat.h"
+#include "bitstream.h"
+
+#define MPC_FRAMESIZE  1152
+
+static const int mpc_rate[4] = { 44100, 48000, 37800, 32000 };
+typedef struct {
+    int64_t pos;
+    int size, skip;
+}MPCFrame;
+
+typedef struct {
+    int ver;
+    uint32_t curframe, lastframe;
+    uint32_t fcount;
+    MPCFrame *frames;
+    int curbits;
+    int frames_noted;
+} MPCContext;
+
+static int mpc_probe(AVProbeData *p)
+{
+    const uint8_t *d = p->buf;
+    if (p->buf_size < 32)
+        return 0;
+    if (d[0] == 'M' && d[1] == 'P' && d[2] == '+' && (d[3] == 0x17 || d[3] == 0x7))
+        return AVPROBE_SCORE_MAX;
+    return 0;
+}
+
+static int mpc_read_header(AVFormatContext *s, AVFormatParameters *ap)
+{
+    MPCContext *c = s->priv_data;
+    AVStream *st;
+
+    if(get_le24(&s->pb) != MKTAG('M', 'P', '+', 0)){
+        av_log(s, AV_LOG_ERROR, "Not a Musepack file\n");
+        return -1;
+    }
+    c->ver = get_byte(&s->pb);
+    if(c->ver != 0x07 && c->ver != 0x17){
+        av_log(s, AV_LOG_ERROR, "Can demux Musepack SV7, got version %02X\n", c->ver);
+        return -1;
+    }
+    c->fcount = get_le32(&s->pb);
+    if((int64_t)c->fcount * sizeof(MPCFrame) >= UINT_MAX){
+        av_log(s, AV_LOG_ERROR, "Too many frames, seeking is not possible\n");
+        return -1;
+    }
+    c->frames = av_malloc(c->fcount * sizeof(MPCFrame));
+    c->curframe = 0;
+    c->lastframe = -1;
+    c->curbits = 8;
+
+    st = av_new_stream(s, 0);
+    if (!st)
+        return AVERROR_NOMEM;
+    st->codec->codec_type = CODEC_TYPE_AUDIO;
+    st->codec->codec_id = CODEC_ID_MUSEPACK7;
+    st->codec->channels = 2;
+    st->codec->bits_per_sample = 16;
+
+    st->codec->extradata_size = 16;
+    st->codec->extradata = av_mallocz(st->codec->extradata_size+FF_INPUT_BUFFER_PADDING_SIZE);
+    get_buffer(&s->pb, st->codec->extradata, 16);
+    st->codec->sample_rate = mpc_rate[st->codec->extradata[2] & 3];
+    av_set_pts_info(st, 32, MPC_FRAMESIZE, st->codec->sample_rate);
+    /* scan for seekpoints */
+    s->start_time = 0;
+    s->duration = (int64_t)c->fcount * MPC_FRAMESIZE * AV_TIME_BASE / st->codec->sample_rate;
+
+    return 0;
+}
+
+static int mpc_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    MPCContext *c = s->priv_data;
+    int ret, size, size2, curbits, cur = c->curframe;
+    int64_t tmp, pos;
+
+    if (c->curframe > c->fcount)
+        return -1;
+
+    if(c->curframe != c->lastframe + 1){
+        url_fseek(&s->pb, c->frames[c->curframe].pos, SEEK_SET);
+        c->curbits = c->frames[c->curframe].skip;
+    }
+    c->lastframe = c->curframe;
+    c->curframe++;
+    curbits = c->curbits;
+    pos = url_ftell(&s->pb);
+    tmp = get_le32(&s->pb);
+    if(curbits <= 12){
+        size2 = (tmp >> (12 - curbits)) & 0xFFFFF;
+    }else{
+        tmp = (tmp << 32) | get_le32(&s->pb);
+        size2 = (tmp >> (44 - curbits)) & 0xFFFFF;
+    }
+    curbits += 20;
+    url_fseek(&s->pb, pos, SEEK_SET);
+
+    size = ((size2 + curbits + 31) & ~31) >> 3;
+    if(cur == c->frames_noted){
+        c->frames[cur].pos = pos;
+        c->frames[cur].size = size;
+        c->frames[cur].skip = curbits - 20;
+        av_add_index_entry(s->streams[0], cur, cur, size, 0, AVINDEX_KEYFRAME);
+        c->frames_noted++;
+    }
+    c->curbits = (curbits + size2) & 0x1F;
+
+    if (av_new_packet(pkt, size) < 0)
+        return AVERROR_IO;
+
+    pkt->data[0] = curbits;
+    pkt->data[1] = (c->curframe > c->fcount);
+
+    pkt->stream_index = 0;
+    ret = get_buffer(&s->pb, pkt->data + 4, size);
+    if(c->curbits)
+        url_fseek(&s->pb, -4, SEEK_CUR);
+    if(ret < size){
+        av_free_packet(pkt);
+        return AVERROR_IO;
+    }
+    pkt->size = ret + 4;
+
+    return 0;
+}
+
+static int mpc_read_close(AVFormatContext *s)
+{
+    MPCContext *c = s->priv_data;
+
+    av_freep(&c->frames);
+    return 0;
+}
+
+static int mpc_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;
+    c->curframe = st->index_entries[index].pos;
+
+    return 0;
+}
+
+
+AVInputFormat mpc_demuxer = {
+    "mpc",
+    "musepack",
+    sizeof(MPCContext),
+    mpc_probe,
+    mpc_read_header,
+    mpc_read_packet,
+    mpc_read_close,
+    mpc_read_seek,
+    .extensions = "mpc",
+};