[FFmpeg-devel] [PATCH] 8088flex TMV demuxer and decoder
Daniel Verkamp
daniel
Fri Apr 24 16:59:05 CEST 2009
On Fri, Apr 24, 2009 at 1:44 AM, Reimar D?ffinger
<Reimar.Doeffinger at gmx.de> wrote:
> On Thu, Apr 23, 2009 at 10:48:42AM -0500, Daniel Verkamp wrote:
>> I tried setting the flags as you described, but trying to seek in
>> ffplay just restarts the video from the beginning. ?Do I need to write
>> a seek function for AVInputFormat as well?
>
> If you set AVFMT_GENERIC_INDEX in the demuxer struct you shouldn't need
> that, no.
Hmm, I get the same "any seek resets to beginning" behavior with
ffplay and the nirvana.nuv file from samples.mphq (the nuv demuxer
seems to do what you're saying too, setting AVFMT_GENERIC_INDEX and
PKT_FLAG_KEY). Seeking in general in ffplay seems to work fine (at
least mpeg).
I've attached a patch which adds these flags just to be sure I'm doing
it correctly.
Thanks,
-- Daniel Verkamp
-------------- next part --------------
>From 1cd460a751e068655fd635d2e8c25cce8b8ba7dd Mon Sep 17 00:00:00 2001
From: Daniel Verkamp <daniel at drv.nu>
Date: Fri, 24 Apr 2009 10:00:25 -0500
Subject: [PATCH 3/3] 8088flex TMV demuxer
---
libavformat/Makefile | 1 +
libavformat/allformats.c | 1 +
libavformat/tmv.c | 145 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 147 insertions(+), 0 deletions(-)
create mode 100644 libavformat/tmv.c
diff --git a/libavformat/Makefile b/libavformat/Makefile
index 55717e6..b9e5eb7 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -210,6 +210,7 @@ OBJS-$(CONFIG_TG2_MUXER) += movenc.o riff.o isom.o avc.o
OBJS-$(CONFIG_TGP_MUXER) += movenc.o riff.o isom.o avc.o
OBJS-$(CONFIG_THP_DEMUXER) += thp.o
OBJS-$(CONFIG_TIERTEXSEQ_DEMUXER) += tiertexseq.o
+OBJS-$(CONFIG_TMV_DEMUXER) += tmv.o
OBJS-$(CONFIG_TRUEHD_DEMUXER) += raw.o id3v2.o
OBJS-$(CONFIG_TRUEHD_MUXER) += raw.o
OBJS-$(CONFIG_TTA_DEMUXER) += tta.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index e193af7..626b66c 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -182,6 +182,7 @@ void av_register_all(void)
REGISTER_MUXER (TGP, tgp);
REGISTER_DEMUXER (THP, thp);
REGISTER_DEMUXER (TIERTEXSEQ, tiertexseq);
+ REGISTER_DEMUXER (TMV, tmv);
REGISTER_MUXDEMUX (TRUEHD, truehd);
REGISTER_DEMUXER (TTA, tta);
REGISTER_DEMUXER (TXD, txd);
diff --git a/libavformat/tmv.c b/libavformat/tmv.c
new file mode 100644
index 0000000..e7ecdda
--- /dev/null
+++ b/libavformat/tmv.c
@@ -0,0 +1,145 @@
+/*
+ * 8088flex TMV file demuxer
+ * Copyright (c) 2009 Daniel Verkamp <daniel at drv.nu>
+ *
+ * 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
+ */
+
+/**
+ * 8088flex TMV file demuxer
+ * @file libavformat/tmv.c
+ * @author Daniel Verkamp
+ * @sa http://www.oldskool.org/pc/8088_Corruption
+ */
+
+#include "libavutil/intreadwrite.h"
+#include "avformat.h"
+
+enum {
+ TMV_PADDING = 0x01,
+ TMV_STEREO = 0x02,
+};
+
+#define TMV_TAG MKTAG('T', 'M', 'A', 'V')
+
+typedef struct TMVContext {
+ unsigned audio_chunk_size;
+ unsigned comp_method;
+ unsigned char_cols;
+ unsigned char_rows;
+ unsigned features;
+
+ unsigned padding;
+
+ unsigned stream_index;
+} TMVContext;
+
+static int tmv_probe(AVProbeData *p)
+{
+ if (AV_RL32(p->buf) == TMV_TAG)
+ return AVPROBE_SCORE_MAX;
+ return 0;
+}
+
+static int tmv_read_header(AVFormatContext *s, AVFormatParameters *ap)
+{
+ TMVContext *tmv = s->priv_data;
+ ByteIOContext *pb = s->pb;
+ AVStream *vst, *ast;
+
+ if (get_le32(pb) != TMV_TAG)
+ return -1;
+
+ if (!(vst = av_new_stream(s, 0)))
+ return AVERROR(ENOMEM);
+
+ if (!(ast = av_new_stream(s, 0)))
+ return AVERROR(ENOMEM);
+
+ ast->codec->sample_rate = get_le16(pb);
+ tmv->audio_chunk_size = get_le16(pb);
+ tmv->comp_method = get_byte(pb);
+ if (tmv->comp_method) {
+ av_log(s, AV_LOG_ERROR, "unsupported compression method %d\n",
+ tmv->comp_method);
+ return -1;
+ }
+
+ tmv->char_cols = get_byte(pb);
+ tmv->char_rows = get_byte(pb);
+
+ tmv->features = get_byte(pb);
+ if (tmv->features & ~(TMV_PADDING | TMV_STEREO)) {
+ av_log(s, AV_LOG_ERROR, "unsupported features 0x%02x\n",
+ tmv->features & ~(TMV_PADDING | TMV_STEREO));
+ return -1;
+ }
+
+ ast->codec->codec_type = CODEC_TYPE_AUDIO;
+ ast->codec->codec_id = CODEC_ID_PCM_U8;
+ ast->codec->sample_fmt = SAMPLE_FMT_U8;
+ ast->codec->channels = tmv->features & TMV_STEREO ? 2 : 1;
+ ast->codec->bits_per_coded_sample = 8;
+ ast->codec->bit_rate = ast->codec->sample_rate *
+ ast->codec->bits_per_coded_sample;
+ av_set_pts_info(ast, 32, 1, ast->codec->sample_rate);
+
+ vst->codec->codec_type = CODEC_TYPE_VIDEO;
+ vst->codec->codec_id = CODEC_ID_TMV;
+ vst->codec->pix_fmt = PIX_FMT_PAL8;
+ vst->codec->width = tmv->char_cols * 8;
+ vst->codec->height = tmv->char_rows * 8;
+ av_set_pts_info(vst, 32, tmv->audio_chunk_size,
+ ast->codec->sample_rate * ast->codec->channels);
+
+ if (tmv->features & TMV_PADDING)
+ tmv->padding = ((2000 + tmv->audio_chunk_size + 511) & ~511) -
+ (2000 + tmv->audio_chunk_size);
+
+ return 0;
+}
+
+static int tmv_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+ TMVContext *tmv = s->priv_data;
+ ByteIOContext *pb = s->pb;
+ int ret, pkt_size = tmv->stream_index ? tmv->audio_chunk_size : 2000;
+
+ if (url_feof(pb))
+ return AVERROR_EOF;
+
+ ret = av_get_packet(pb, pkt, pkt_size);
+
+ if (tmv->features & TMV_PADDING && tmv->stream_index)
+ url_fskip(pb, tmv->padding);
+
+ pkt->stream_index = tmv->stream_index;
+ tmv->stream_index ^= 1;
+ pkt->flags |= PKT_FLAG_KEY;
+
+ return ret;
+}
+
+AVInputFormat tmv_demuxer = {
+ "tmv",
+ NULL_IF_CONFIG_SMALL("8088flex TMV"),
+ sizeof(TMVContext),
+ tmv_probe,
+ tmv_read_header,
+ tmv_read_packet,
+ .flags = AVFMT_GENERIC_INDEX,
+};
--
1.6.2.3
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