[FFmpeg-devel] [PATCH] VC-1 SP/MP test bitstreams demuxer
Kostya
kostya.shishkov
Mon Jan 28 10:26:08 CET 2008
On Sun, Jan 27, 2008 at 03:23:01PM +0100, Michael Niedermayer wrote:
> On Sun, Jan 27, 2008 at 03:47:34PM +0200, Kostya wrote:
> > On Sun, Jan 27, 2008 at 12:57:50PM +0100, Michael Niedermayer wrote:
> > > On Sun, Jan 27, 2008 at 10:19:54AM +0200, Kostya wrote:
> > > [...]
> > >
> > > >
> > > > > > + if(av_get_packet(pb, pkt, frame_size) < 0)
> > > > > > + return AVERROR(EIO);
> > > > > > + pkt->flags |= keyframe ? PKT_FLAG_KEY : 0;
> > > > > > +
> > > > > > + return pkt->size;
> > > > > > +}
> > > > > > +
> > > > > > +AVInputFormat vc1t_demuxer = {
> > > > > > + "vc1test",
> > > > > > + "VC1 test bitstream format",
> > > > > > + 0,
> > > > > > + vc1t_probe,
> > > > > > + vc1t_read_header,
> > > > > > + vc1t_read_packet,
> > > > > > +};
> > > > >
> > > > > does seeking work?
> > > > > if no try setting AVFMT_GENERIC_INDEX and try again
> > > > > if still not, check if the generic code builds the index properly
> > > > > and fix it, this should be just a 1 or 2 line fix in utils.c
> > > >
> > > > It won't work as index is built only for parsed formats.
> > >
> > > yes, i meant you could fix that :)
> > > though thats of course independant of this patch ...
> >
> > You could as well ;)
>
> yes i could ... ;)
> but its always better if someone else does the work :))))
>
>
> > Here's an untested proof of concept
>
> ok if it works and is tested :)
>
>
> >
> > > [...]
> > > > + if(!s->streams[0]->r_frame_rate.num)
> > > > + pkt->pts = pts;
> > >
> > > you are missusing r_frame_rate.num here
> > > actually i dont see what would prevent lavf to set it to a non zero value
> > > in av_find_stream_info() and then break this ...
> >
> > How should I redo it then?
>
> well
> many ways
> one would be to check if timebase.den == 1000
Here it is. And it works with my patch for generic index (which should be
tested more).
> [...]
> --
> Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
-------------- next part --------------
Index: libavformat/vc1test.c
===================================================================
--- libavformat/vc1test.c (revision 0)
+++ libavformat/vc1test.c (revision 0)
@@ -0,0 +1,112 @@
+/*
+ * VC1 Test Bitstreams Format Demuxer
+ * Copyright (c) 2006, 2008 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
+ */
+
+/**
+ * @file vc1test.c
+ * VC1 test bitstream file demuxer
+ * by Konstantin Shishkov
+ * Format specified in SMPTE standard 421 Annex L
+ */
+
+#include "avformat.h"
+
+#define VC1_EXTRADATA_SIZE 4
+
+static int vc1t_probe(AVProbeData *p)
+{
+ if (p->buf[3] != 0xC5 && AV_RL32(&p->buf[4]) != 4)
+ return 0;
+
+ return AVPROBE_SCORE_MAX;
+}
+
+static int vc1t_read_header(AVFormatContext *s,
+ AVFormatParameters *ap)
+{
+ ByteIOContext *pb = s->pb;
+ AVStream *st;
+ int fps, frames;
+
+ frames = get_le24(pb);
+ if(get_byte(pb) != 0xC5 || get_le32(pb) != 4)
+ return -1;
+
+ /* init video codec */
+ st = av_new_stream(s, 0);
+ if (!st)
+ return -1;
+
+ st->codec->codec_type = CODEC_TYPE_VIDEO;
+ st->codec->codec_id = CODEC_ID_WMV3;
+
+ st->codec->extradata = av_malloc(VC1_EXTRADATA_SIZE);
+ st->codec->extradata_size = VC1_EXTRADATA_SIZE;
+ get_buffer(pb, st->codec->extradata, VC1_EXTRADATA_SIZE);
+ st->codec->height = get_le32(pb);
+ st->codec->width = get_le32(pb);
+ if(get_le32(pb) != 0xC)
+ return -1;
+ url_fskip(pb, 8);
+ fps = get_le32(pb);
+ if(fps == -1)
+ av_set_pts_info(st, 32, 1, 1000);
+ else{
+ av_set_pts_info(st, 24, 1, fps);
+ st->duration = frames;
+ }
+
+ return 0;
+}
+
+static int vc1t_read_packet(AVFormatContext *s,
+ AVPacket *pkt)
+{
+ ByteIOContext *pb = s->pb;
+ int frame_size;
+ int keyframe = 0;
+ uint32_t pts;
+
+ if(url_feof(pb))
+ return AVERROR(EIO);
+
+ frame_size = get_le24(pb);
+ if(get_byte(pb) & 0x80)
+ keyframe = 1;
+ pts = get_le32(pb);
+ if(av_get_packet(pb, pkt, frame_size) < 0)
+ return AVERROR(EIO);
+ if(s->streams[0]->time_base.den == 1000)
+ pkt->pts = pts;
+ pkt->flags |= keyframe ? PKT_FLAG_KEY : 0;
+ pkt->pos -= 8;
+
+ return pkt->size;
+}
+
+AVInputFormat vc1t_demuxer = {
+ "vc1test",
+ "VC1 test bitstream format",
+ 0,
+ vc1t_probe,
+ vc1t_read_header,
+ vc1t_read_packet,
+ .flags = AVFMT_GENERIC_INDEX,
+};
Index: libavformat/Makefile
===================================================================
--- libavformat/Makefile (revision 11619)
+++ libavformat/Makefile (working copy)
@@ -162,6 +162,7 @@
OBJS-$(CONFIG_TTA_DEMUXER) += tta.o
OBJS-$(CONFIG_TXD_DEMUXER) += txd.o
OBJS-$(CONFIG_VC1_DEMUXER) += raw.o
+OBJS-$(CONFIG_VC1T_DEMUXER) += vc1test.o
OBJS-$(CONFIG_VMD_DEMUXER) += sierravmd.o
OBJS-$(CONFIG_VOC_DEMUXER) += vocdec.o voc.o
OBJS-$(CONFIG_VOC_MUXER) += vocenc.o voc.o
Index: libavformat/allformats.c
===================================================================
--- libavformat/allformats.c (revision 11619)
+++ libavformat/allformats.c (working copy)
@@ -156,6 +156,7 @@
REGISTER_DEMUXER (TTA, tta);
REGISTER_DEMUXER (TXD, txd);
REGISTER_DEMUXER (VC1, vc1);
+ REGISTER_DEMUXER (VC1T, vc1t);
REGISTER_DEMUXER (VMD, vmd);
REGISTER_MUXDEMUX (VOC, voc);
REGISTER_MUXDEMUX (WAV, wav);
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