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Diffstat (limited to 'contrib/ffmpeg/libavformat/mpc.c')
-rw-r--r--contrib/ffmpeg/libavformat/mpc.c231
1 files changed, 231 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavformat/mpc.c b/contrib/ffmpeg/libavformat/mpc.c
new file mode 100644
index 000000000..a28efb16d
--- /dev/null
+++ b/contrib/ffmpeg/libavformat/mpc.c
@@ -0,0 +1,231 @@
+/*
+ * 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
+#define DELAY_FRAMES 32
+
+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;
+ if (d[0] == 'I' && d[1] == 'D' && d[2] == '3')
+ return AVPROBE_SCORE_MAX / 2;
+ return 0;
+}
+
+static int mpc_read_header(AVFormatContext *s, AVFormatParameters *ap)
+{
+ MPCContext *c = s->priv_data;
+ AVStream *st;
+ int t;
+
+ t = get_le24(&s->pb);
+ if(t != MKTAG('M', 'P', '+', 0)){
+ if(t != MKTAG('I', 'D', '3', 0)){
+ av_log(s, AV_LOG_ERROR, "Not a Musepack file\n");
+ return -1;
+ }
+ /* skip ID3 tags and try again */
+ url_fskip(&s->pb, 3);
+ t = get_byte(&s->pb) << 21;
+ t |= get_byte(&s->pb) << 14;
+ t |= get_byte(&s->pb) << 7;
+ t |= get_byte(&s->pb);
+ av_log(s, AV_LOG_DEBUG, "Skipping %d(%X) bytes of ID3 data\n", t, t);
+ url_fskip(&s->pb, t);
+ 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;
+ c->frames_noted = 0;
+
+ 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;
+ pkt->pts = cur;
+ 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;
+}
+
+/**
+ * Seek to the given position
+ * If position is unknown but is within the limits of file
+ * then packets are skipped unless desired position is reached
+ *
+ * Also this function makes use of the fact that timestamp == frameno
+ */
+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;
+ AVPacket pkt1, *pkt = &pkt1;
+ int ret;
+ int index = av_index_search_timestamp(st, timestamp - DELAY_FRAMES, flags);
+ uint32_t lastframe;
+
+ /* if found, seek there */
+ if (index >= 0){
+ c->curframe = st->index_entries[index].pos;
+ return 0;
+ }
+ /* if timestamp is out of bounds, return error */
+ if(timestamp < 0 || timestamp >= c->fcount)
+ return -1;
+ timestamp -= DELAY_FRAMES;
+ /* seek to the furthest known position and read packets until
+ we reach desired position */
+ lastframe = c->curframe;
+ if(c->frames_noted) c->curframe = c->frames_noted - 1;
+ while(c->curframe < timestamp){
+ ret = av_read_frame(s, pkt);
+ if (ret < 0){
+ c->curframe = lastframe;
+ return -1;
+ }
+ av_free_packet(pkt);
+ }
+ 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",
+};
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