[FFmpeg-cvslog] ACT demuxer

Vladimir Voroshilov git at videolan.org
Sat Sep 24 21:17:04 CEST 2011


ffmpeg | branch: master | Vladimir Voroshilov <voroshil at gmail.com> | Thu Jun  4 01:43:53 2009 +0700| [6080553e6e56a9bbdb9bda13420fd586a11a7d67] | committer: Michael Niedermayer

ACT demuxer

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=6080553e6e56a9bbdb9bda13420fd586a11a7d67
---

 libavformat/Makefile     |    1 +
 libavformat/act.c        |  207 ++++++++++++++++++++++++++++++++++++++++++++++
 libavformat/allformats.c |    1 +
 3 files changed, 209 insertions(+), 0 deletions(-)

diff --git a/libavformat/Makefile b/libavformat/Makefile
index cc5a964..6fdc637 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -21,6 +21,7 @@ OBJS-$(CONFIG_A64_MUXER)                 += a64.o
 OBJS-$(CONFIG_AAC_DEMUXER)               += aacdec.o rawdec.o
 OBJS-$(CONFIG_AC3_DEMUXER)               += ac3dec.o rawdec.o
 OBJS-$(CONFIG_AC3_MUXER)                 += rawenc.o
+OBJS-$(CONFIG_ACT_DEMUXER)               += act.o
 OBJS-$(CONFIG_ADF_DEMUXER)               += bintext.o sauce.o
 OBJS-$(CONFIG_ADTS_MUXER)                += adtsenc.o
 OBJS-$(CONFIG_AEA_DEMUXER)               += aea.o pcm.o
diff --git a/libavformat/act.c b/libavformat/act.c
new file mode 100644
index 0000000..a89fae7
--- /dev/null
+++ b/libavformat/act.c
@@ -0,0 +1,207 @@
+/*
+ * ACT file format muxer/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 "riff.h"
+#include "libavcodec/get_bits.h"
+
+#define CHUNK_SIZE 512
+#define RIFF_TAG MKTAG('R','I','F','F')
+#define WAVE_TAG MKTAG('W','A','V','E')
+
+typedef struct{
+    int bytes_left_in_chunk;
+    uint8_t audio_buffer[22];///< temporary buffer for ACT frame
+    char second_packet;      ///< 1 - if temporary buffer contains valid (second) G.729 packet
+} ACTContext;
+
+static int probe(AVProbeData *p)
+{
+    int i;
+
+    if ((AV_RL32(&p->buf[0]) != RIFF_TAG) ||
+        (AV_RL32(&p->buf[8]) != WAVE_TAG) ||
+        (AV_RL32(&p->buf[16]) != 16))
+    return 0;
+
+    //We cant be sure that this is ACT and not regular WAV
+    if (p->buf_size<512)
+        return 0;
+
+    for(i=44; i<256; i++)
+        if(p->buf[i])
+            return 0;
+
+    if(p->buf[256]!=0x84)
+        return 0;
+
+    for(i=264; i<512; i++)
+        if(p->buf[i])
+            return 0;
+
+    return AVPROBE_SCORE_MAX;
+}
+
+static int read_header(AVFormatContext *s,
+                           AVFormatParameters *ap)
+{
+    ACTContext* ctx = s->priv_data;
+    ByteIOContext *pb = s->pb;
+    int size;
+    AVStream* st;
+
+    int min,sec,msec;
+
+    st=av_new_stream(s, 0);
+    if (!st)
+        return AVERROR(ENOMEM);
+
+    url_fskip(pb, 16);
+    size=get_le32(pb);
+    ff_get_wav_header(pb, st->codec, size);
+
+    /*
+      8000Hz (Fine-rec) file format has 10 bytes long
+      packets with 10ms of sound data in them
+    */
+    if (st->codec->sample_rate != 8000) {
+        av_log(s, AV_LOG_ERROR, "Sample rate %d is not supported.\n", st->codec->sample_rate);
+        return AVERROR_NOFMT;
+    }
+
+    st->codec->frame_size=80;
+    st->codec->channels=1;
+    av_set_pts_info(st, 64, 1, 100);
+
+    st->codec->codec_id=CODEC_ID_G729;
+
+    url_fseek(pb, 257, SEEK_SET);
+    msec=get_le16(pb);
+    sec=get_byte(pb);
+    min=get_le32(pb);
+
+    st->duration = av_rescale(1000*(min*60+sec)+msec, st->codec->sample_rate, 1000 * st->codec->frame_size);
+
+    ctx->bytes_left_in_chunk=CHUNK_SIZE;
+
+    url_fseek(pb, 512, SEEK_SET);
+
+    return 0;
+}
+
+
+static int read_packet(AVFormatContext *s,
+                          AVPacket *pkt)
+{
+    ACTContext *ctx = s->priv_data;
+    ByteIOContext *pb = s->pb;
+    int ret;
+    int frame_size=s->streams[0]->codec->sample_rate==8000?10:22;
+
+
+    if(s->streams[0]->codec->sample_rate==8000)
+        ret=av_new_packet(pkt, 10);
+    else
+        ret=av_new_packet(pkt, 11);
+
+    if(ret)
+        return ret;
+
+    if(s->streams[0]->codec->sample_rate==4400 && !ctx->second_packet)
+    {
+        ret = get_buffer(pb, ctx->audio_buffer, frame_size);
+
+        if(ret<0)
+            return ret;
+        if(ret!=frame_size)
+            return AVERROR(EIO);
+
+        pkt->data[0]=ctx->audio_buffer[11];
+        pkt->data[1]=ctx->audio_buffer[0];
+        pkt->data[2]=ctx->audio_buffer[12];
+        pkt->data[3]=ctx->audio_buffer[1];
+        pkt->data[4]=ctx->audio_buffer[13];
+        pkt->data[5]=ctx->audio_buffer[2];
+        pkt->data[6]=ctx->audio_buffer[14];
+        pkt->data[7]=ctx->audio_buffer[3];
+        pkt->data[8]=ctx->audio_buffer[15];
+        pkt->data[9]=ctx->audio_buffer[4];
+        pkt->data[10]=ctx->audio_buffer[16];
+
+        ctx->second_packet=1;
+    }
+    else if(s->streams[0]->codec->sample_rate==4400 && ctx->second_packet)
+    {
+        pkt->data[0]=ctx->audio_buffer[5];
+        pkt->data[1]=ctx->audio_buffer[17];
+        pkt->data[2]=ctx->audio_buffer[6];
+        pkt->data[3]=ctx->audio_buffer[18];
+        pkt->data[4]=ctx->audio_buffer[7];
+        pkt->data[5]=ctx->audio_buffer[19];
+        pkt->data[6]=ctx->audio_buffer[8];
+        pkt->data[7]=ctx->audio_buffer[20];
+        pkt->data[8]=ctx->audio_buffer[9];
+        pkt->data[9]=ctx->audio_buffer[21];
+        pkt->data[10]=ctx->audio_buffer[10];
+
+        ctx->second_packet=0;
+    }
+    else // 8000 Hz
+    {
+        ret = get_buffer(pb, ctx->audio_buffer, frame_size);
+
+        if(ret<0)
+            return ret;
+        if(ret!=frame_size)
+            return AVERROR(EIO);
+
+        pkt->data[0]=ctx->audio_buffer[5];
+        pkt->data[1]=ctx->audio_buffer[0];
+        pkt->data[2]=ctx->audio_buffer[6];
+        pkt->data[3]=ctx->audio_buffer[1];
+        pkt->data[4]=ctx->audio_buffer[7];
+        pkt->data[5]=ctx->audio_buffer[2];
+        pkt->data[6]=ctx->audio_buffer[8];
+        pkt->data[7]=ctx->audio_buffer[3];
+        pkt->data[8]=ctx->audio_buffer[9];
+        pkt->data[9]=ctx->audio_buffer[4];
+    }
+
+    ctx->bytes_left_in_chunk -= frame_size;
+
+    if(ctx->bytes_left_in_chunk < frame_size)
+    {
+        url_fskip(pb, ctx->bytes_left_in_chunk);
+        ctx->bytes_left_in_chunk=CHUNK_SIZE;
+    }
+
+    pkt->duration=1;
+
+    return ret;
+}
+
+AVInputFormat ff_act_demuxer = {
+    "act",
+    "ACT Voice file format",
+    sizeof(ACTContext),
+    probe,
+    read_header,
+    read_packet
+};
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index ecc7c67..84cbb38 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -51,6 +51,7 @@ void av_register_all(void)
     REGISTER_MUXER    (A64, a64);
     REGISTER_DEMUXER  (AAC, aac);
     REGISTER_MUXDEMUX (AC3, ac3);
+    REGISTER_DEMUXER  (ACT, act);
     REGISTER_DEMUXER  (ADF, adf);
     REGISTER_MUXER    (ADTS, adts);
     REGISTER_DEMUXER  (AEA, aea);



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