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-rw-r--r--libavformat/bit.c156
1 files changed, 156 insertions, 0 deletions
diff --git a/libavformat/bit.c b/libavformat/bit.c
new file mode 100644
index 0000000000..0be471ac4f
--- /dev/null
+++ b/libavformat/bit.c
@@ -0,0 +1,156 @@
+/*
+ * G.729 bit format muxer and demuxer
+ * Copyright (c) 2007-2008 Vladimir Voroshilov
+ *
+ * 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 "internal.h"
+#include "libavcodec/get_bits.h"
+#include "libavcodec/put_bits.h"
+
+#define MAX_FRAME_SIZE 10
+
+#define SYNC_WORD 0x6b21
+#define BIT_0 0x7f
+#define BIT_1 0x81
+
+static int probe(AVProbeData *p)
+{
+ int i, j;
+
+ if(p->buf_size < 0x40)
+ return 0;
+
+ for(i=0; i+3<p->buf_size && i< 10*0x50; ){
+ if(AV_RL16(&p->buf[0]) != SYNC_WORD)
+ return 0;
+ j=AV_RL16(&p->buf[2]);
+ if(j!=0x40 && j!=0x50)
+ return 0;
+ i+=j;
+ }
+ return AVPROBE_SCORE_EXTENSION;
+}
+
+static int read_header(AVFormatContext *s)
+{
+ AVStream* st;
+
+ st=avformat_new_stream(s, NULL);
+ if (!st)
+ return AVERROR(ENOMEM);
+
+ st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
+ st->codec->codec_id=AV_CODEC_ID_G729;
+ st->codec->sample_rate=8000;
+ st->codec->block_align = 16;
+ st->codec->channels=1;
+
+ avpriv_set_pts_info(st, 64, 1, 100);
+ return 0;
+}
+
+static int read_packet(AVFormatContext *s,
+ AVPacket *pkt)
+{
+ AVIOContext *pb = s->pb;
+ PutBitContext pbo;
+ uint16_t buf[8 * MAX_FRAME_SIZE + 2];
+ int packet_size;
+ uint16_t* src=buf;
+ int i, j, ret;
+ int64_t pos= avio_tell(pb);
+
+ if(url_feof(pb))
+ return AVERROR_EOF;
+
+ avio_rl16(pb); // sync word
+ packet_size = avio_rl16(pb) / 8;
+ if(packet_size > MAX_FRAME_SIZE)
+ return AVERROR_INVALIDDATA;
+
+ ret = avio_read(pb, (uint8_t*)buf, (8 * packet_size) * sizeof(uint16_t));
+ if(ret<0)
+ return ret;
+ if(ret != 8 * packet_size * sizeof(uint16_t))
+ return AVERROR(EIO);
+
+ if (av_new_packet(pkt, packet_size) < 0)
+ return AVERROR(ENOMEM);
+
+ init_put_bits(&pbo, pkt->data, packet_size);
+ for(j=0; j < packet_size; j++)
+ for(i=0; i<8;i++)
+ put_bits(&pbo,1, AV_RL16(src++) == BIT_1 ? 1 : 0);
+
+ flush_put_bits(&pbo);
+
+ pkt->duration=1;
+ pkt->pos = pos;
+ return 0;
+}
+
+AVInputFormat ff_bit_demuxer = {
+ .name = "bit",
+ .long_name = NULL_IF_CONFIG_SMALL("G.729 BIT file format"),
+ .read_probe = probe,
+ .read_header = read_header,
+ .read_packet = read_packet,
+ .extensions = "bit",
+};
+
+#if CONFIG_MUXERS
+static int write_header(AVFormatContext *s)
+{
+ AVCodecContext *enc = s->streams[0]->codec;
+
+ enc->codec_id = AV_CODEC_ID_G729;
+ enc->channels = 1;
+ enc->bits_per_coded_sample = 16;
+ enc->block_align = (enc->bits_per_coded_sample * enc->channels) >> 3;
+
+ return 0;
+}
+
+static int write_packet(AVFormatContext *s, AVPacket *pkt)
+{
+ AVIOContext *pb = s->pb;
+ GetBitContext gb;
+ int i;
+
+ avio_wl16(pb, SYNC_WORD);
+ avio_wl16(pb, 8 * 10);
+
+ init_get_bits(&gb, pkt->data, 8*10);
+ for(i=0; i< 8 * 10; i++)
+ avio_wl16(pb, get_bits1(&gb) ? BIT_1 : BIT_0);
+
+ return 0;
+}
+
+AVOutputFormat ff_bit_muxer = {
+ .name = "bit",
+ .long_name = NULL_IF_CONFIG_SMALL("G.729 BIT file format"),
+ .mime_type = "audio/bit",
+ .extensions = "bit",
+ .audio_codec = AV_CODEC_ID_G729,
+ .video_codec = AV_CODEC_ID_NONE,
+ .write_header = write_header,
+ .write_packet = write_packet,
+};
+#endif