[FFmpeg-devel] [PATCH] Demuxer for Leitch/Harris' VR native stream format (LXF)
Stefano Sabatini
stefano.sabatini-lala
Wed Sep 29 11:05:13 CEST 2010
On date Wednesday 2010-09-29 09:55:28 +0200, Tomas H?rdin encoded:
> On Tue, 2010-09-28 at 19:55 +0200, Michael Niedermayer wrote:
> > On Tue, Sep 28, 2010 at 02:59:13PM +0200, Tomas H?rdin wrote:
> > [...]
> > > +#define LXF_PACKET_HEADER_SIZE 60
> > > +#define LXF_HEADER_DATA_SIZE 120
> > > +#define LXF_IDENT "LEITCH\0"
> > > +#define LXF_IDENT_LENGTH 8
> > > +#define LXF_SAMPLERATE 48000
> > > +#define LXF_MAX_AUDIO_PACKET (8008*15*4) //15-channel 32-bit NTSC audio frame
> > > +
> > > +static const AVCodecTag lxf_tags[] = {
> > > + { CODEC_ID_MJPEG, 0 },
> > > + { CODEC_ID_MPEG1VIDEO, 1 },
> > > + { CODEC_ID_MPEG2VIDEO, 2 }, //MpMl, 4:2:0
> > > + { CODEC_ID_MPEG2VIDEO, 3 }, //MpPl, 4:2:2
> > > + { CODEC_ID_DVVIDEO, 4 }, //DV25
> > > + { CODEC_ID_DVVIDEO, 5 }, //DVCPRO
> > > + { CODEC_ID_DVVIDEO, 6 }, //DVCPRO50
> > > + { CODEC_ID_RAWVIDEO, 7 }, //PIX_FMT_ARGB, where alpha is used for chroma keying
> > > + { CODEC_ID_RAWVIDEO, 8 }, //16-bit chroma key
> > > + { CODEC_ID_MPEG2VIDEO, 9 }, //4:2:2 CBP ("Constrained Bytes per Gop")
> > > + { CODEC_ID_NONE, 0 },
> > > +};
> > > +
> > > +typedef struct {
> > > + int channels; //number of audio channels. 0 -> no audio
> > > + uint8_t temp[LXF_MAX_AUDIO_PACKET]; //temp buffer for de-planarizing the audio data
> > > + int frame_number;
> > > +} LXFDemuxContext;
> >
> > the comments dont look doxygen compatible
>
> Fixed. doxygen didn't make use of doxyfied comments in lxf_tags, so I
> left them as is. Otherwise they get stripped from the code listing. I
> also added a comment for frame_number. Updated patch attached.
>
> /Tomas
> diff --git a/Changelog b/Changelog
> index a76cec1..13f53a5 100644
> --- a/Changelog
> +++ b/Changelog
> @@ -42,6 +42,7 @@ version <next>:
> - make ffprobe accept AVFormatContext options
> - yadif filter
> - blackframe filter
> +- Demuxer for Leitch/Harris' VR native stream format (LXF)
>
>
> version 0.6:
> diff --git a/doc/general.texi b/doc/general.texi
> index b9953cc..890319b 100644
> --- a/doc/general.texi
> +++ b/doc/general.texi
> @@ -114,6 +114,8 @@ library:
> @tab A format used by libvpx
> @item LMLM4 @tab @tab X
> @tab Used by Linux Media Labs MPEG-4 PCI boards
> + at item LXF @tab @tab X
> + @tab VR native stream format, used by Leitch/Harris' video servers.
Off-topic but this table can be avoided if we find a way to
automatically generate it, the description given here may go to a new
description field in AVInputFormat (even better: we should have a
format ID and have some way to map a name/description to the ID, same
for codecs).
> @item Matroska @tab X @tab X
> @item Matroska audio @tab X @tab
> @item MAXIS XA @tab @tab X
> diff --git a/libavformat/Makefile b/libavformat/Makefile
> index fb9b176..b3ae72a 100644
> --- a/libavformat/Makefile
> +++ b/libavformat/Makefile
> @@ -105,6 +105,7 @@ OBJS-$(CONFIG_ISS_DEMUXER) += iss.o
> OBJS-$(CONFIG_IV8_DEMUXER) += iv8.o
> OBJS-$(CONFIG_IVF_DEMUXER) += ivfdec.o riff.o
> OBJS-$(CONFIG_LMLM4_DEMUXER) += lmlm4.o
> +OBJS-$(CONFIG_LXF_DEMUXER) += lxfdec.o
> OBJS-$(CONFIG_M4V_DEMUXER) += m4vdec.o rawdec.o
> OBJS-$(CONFIG_M4V_MUXER) += rawenc.o
> OBJS-$(CONFIG_MATROSKA_DEMUXER) += matroskadec.o matroska.o \
> diff --git a/libavformat/allformats.c b/libavformat/allformats.c
> index f9407f0..f9e1fb3 100644
> --- a/libavformat/allformats.c
> +++ b/libavformat/allformats.c
> @@ -110,6 +110,7 @@ void av_register_all(void)
> REGISTER_DEMUXER (IV8, iv8);
> REGISTER_DEMUXER (IVF, ivf);
> REGISTER_DEMUXER (LMLM4, lmlm4);
> + REGISTER_DEMUXER (LXF, lxf);
> REGISTER_MUXDEMUX (M4V, m4v);
> REGISTER_MUXER (MD5, md5);
> REGISTER_MUXDEMUX (MATROSKA, matroska);
> diff --git a/libavformat/avformat.h b/libavformat/avformat.h
> index 0520530..362a056 100644
> --- a/libavformat/avformat.h
> +++ b/libavformat/avformat.h
> @@ -22,8 +22,8 @@
> #define AVFORMAT_AVFORMAT_H
>
> #define LIBAVFORMAT_VERSION_MAJOR 52
> -#define LIBAVFORMAT_VERSION_MINOR 78
> -#define LIBAVFORMAT_VERSION_MICRO 5
> +#define LIBAVFORMAT_VERSION_MINOR 79
> +#define LIBAVFORMAT_VERSION_MICRO 0
>
> #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
> LIBAVFORMAT_VERSION_MINOR, \
> diff --git a/libavformat/lxfdec.c b/libavformat/lxfdec.c
> new file mode 100644
> index 0000000..900f55e
> --- /dev/null
> +++ b/libavformat/lxfdec.c
> @@ -0,0 +1,354 @@
> +/*
> + * LXF demuxer
> + * Copyright (c) 2010 Tomas H?rdin
> + *
> + * 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 "libavutil/intreadwrite.h"
> +#include "avformat.h"
> +#include "riff.h"
> +
> +#define LXF_PACKET_HEADER_SIZE 60
> +#define LXF_HEADER_DATA_SIZE 120
> +#define LXF_IDENT "LEITCH\0"
> +#define LXF_IDENT_LENGTH 8
> +#define LXF_SAMPLERATE 48000
> +#define LXF_MAX_AUDIO_PACKET (8008*15*4) ///< 15-channel 32-bit NTSC audio frame
> +
> +static const AVCodecTag lxf_tags[] = {
> + { CODEC_ID_MJPEG, 0 },
> + { CODEC_ID_MPEG1VIDEO, 1 },
> + { CODEC_ID_MPEG2VIDEO, 2 }, //MpMl, 4:2:0
> + { CODEC_ID_MPEG2VIDEO, 3 }, //MpPl, 4:2:2
> + { CODEC_ID_DVVIDEO, 4 }, //DV25
> + { CODEC_ID_DVVIDEO, 5 }, //DVCPRO
> + { CODEC_ID_DVVIDEO, 6 }, //DVCPRO50
> + { CODEC_ID_RAWVIDEO, 7 }, //PIX_FMT_ARGB, where alpha is used for chroma keying
> + { CODEC_ID_RAWVIDEO, 8 }, //16-bit chroma key
> + { CODEC_ID_MPEG2VIDEO, 9 }, //4:2:2 CBP ("Constrained Bytes per Gop")
> + { CODEC_ID_NONE, 0 },
> +};
> +
> +typedef struct {
> + int channels; ///< number of audio channels. zero means no audio
> + uint8_t temp[LXF_MAX_AUDIO_PACKET]; ///< temp buffer for de-planarizing the audio data
> + int frame_number; ///< current video frame
> +} LXFDemuxContext;
> +
> +static int lxf_probe(AVProbeData *p)
> +{
> + if (!memcmp(p->buf, LXF_IDENT, LXF_IDENT_LENGTH))
> + return AVPROBE_SCORE_MAX;
> +
> + return 0;
> +}
> +
> +/**
> + * Verify the checksum of an LXF packet header
> + *
> + * @param[in] header the packet header to check
> + * @return zero if the checksum is OK, non-zero otherwise
> + */
> +static int check_checksum(const uint8_t *header)
> +{
> + int x;
> + uint32_t sum = 0;
> +
> + for (x = 0; x < LXF_PACKET_HEADER_SIZE; x += 4)
> + sum += AV_RL32(&header[x]);
> +
> + return sum;
> +}
> +
> +/**
> + * Read input until we find the next ident. If found, copy it to the header buffer
> + *
> + * @param[out] header where to copy the ident to
> + * @return 0 if an ident was found, < 0 on I/O error
> + */
> +static int sync(AVFormatContext *s, uint8_t *header)
> +{
> + uint8_t buf[LXF_IDENT_LENGTH];
> +
> + if (get_buffer(s->pb, buf, LXF_IDENT_LENGTH) < 0)
> + return AVERROR_IO;
> +
> + while (memcmp(buf, LXF_IDENT, LXF_IDENT_LENGTH)) {
> + if (url_feof(s->pb))
> + return AVERROR_EOF;
> +
> + memmove(buf, &buf[1], LXF_IDENT_LENGTH-1);
> + buf[LXF_IDENT_LENGTH-1] = get_byte(s->pb);
> + }
> +
> + memcpy(header, LXF_IDENT, LXF_IDENT_LENGTH);
> +
> + return 0;
> +}
> +
> +/**
> + * Read and checksum the next packet header
> + *
> + * @param[out] header the read packet header
> + * @param[out] format context dependent format information
> + * @return the size of the payload following the header or < 0 on failure
> + */
> +static int get_packet_header(AVFormatContext *s, uint8_t *header, uint32_t *format)
> +{
> + ByteIOContext *pb = s->pb;
> + int track_size, samples, ret;
> + AVStream *st;
> +
> + //find and read the ident
> + if ((ret = sync(s, header)) < 0)
> + return ret;
> +
> + //read the rest of the packet header
> + if ((ret = get_buffer(pb, header + LXF_IDENT_LENGTH,
> + LXF_PACKET_HEADER_SIZE - LXF_IDENT_LENGTH)) !=
> + LXF_PACKET_HEADER_SIZE - LXF_IDENT_LENGTH)
> + return ret;
> +
> + if (check_checksum(header))
> + av_log(s, AV_LOG_ERROR, "checksum error\n");
> +
> + *format = AV_RL32(&header[32]);
> + ret = AV_RL32(&header[36]);
> +
> + //type
> + switch (AV_RL32(&header[16])) {
> + case 0:
> + //video
> + //skip VBI data and metadata
> + url_fskip(pb, (int64_t)(uint32_t)AV_RL32(&header[44]) +
> + (int64_t)(uint32_t)AV_RL32(&header[52]));
> + break;
> + case 1:
> + //audio
> + if (!(st = s->streams[1])) {
> + av_log(s, AV_LOG_INFO, "got audio packet, but no audio stream present\n");
> + break;
> + }
> +
> + //set codec based on specified audio bitdepth
> + //we only support tightly packed 16-, 20-, 24- and 32-bit PCM at the moment
> + *format = AV_RL32(&header[40]);
> + st->codec->bits_per_coded_sample = (*format >> 6) & 0x3F;
> +
> + if (st->codec->bits_per_coded_sample != (*format & 0x3F)) {
> + av_log(s, AV_LOG_WARNING, "only tightly packed PCM currently supported\n");
> + return AVERROR_PATCHWELCOME;
> + }
> +
> + switch (st->codec->bits_per_coded_sample) {
> + case 16:
> + st->codec->codec_id = CODEC_ID_PCM_S16LE;
> + break;
> + case 20:
> + st->codec->codec_id = CODEC_ID_PCM_LXF;
> + break;
> + case 24:
> + st->codec->codec_id = CODEC_ID_PCM_S24LE;
> + break;
> + case 32:
> + st->codec->codec_id = CODEC_ID_PCM_S32LE;
> + break;
This can be:
case X: st->codec->codec_id = CODEC_ID_PCM_Y; break;
for better alignment / readability.
> + default:
> + av_log(s, AV_LOG_WARNING,
> + "only 16-, 20-, 24- and 32-bit PCM currently supported\n");
> + return AVERROR_PATCHWELCOME;
> + }
> +
> + track_size = AV_RL32(&header[48]);
> + samples = track_size * 8 / st->codec->bits_per_coded_sample;
> +
> + //use audio packet size to determine video standard
> + //for NTSC we have one 8008-sample audio frame per five video frames
> + if (samples == LXF_SAMPLERATE * 5005 / 30000) {
> + av_set_pts_info(s->streams[0], 64, 1001, 30000);
> + } else {
> + //assume PAL, but warn if we don't have 1920 samples
> + if (samples != LXF_SAMPLERATE / 25)
> + av_log(s, AV_LOG_WARNING,
> + "video doesn't seem to be PAL or NTSC. guessing PAL\n");
> +
> + av_set_pts_info(s->streams[0], 64, 1, 25);
> + }
> +
> + //TODO: warning if track mask != (1 << channels) - 1?
> + ret = av_popcount(AV_RL32(&header[44])) * track_size;
> +
> + break;
> + default:
> + break;
> + }
> +
> + return ret;
> +}
> +
> +static int lxf_read_header(AVFormatContext *s, AVFormatParameters *ap)
> +{
> + LXFDemuxContext *lxf = s->priv_data;
> + ByteIOContext *pb = s->pb;
> + uint8_t header[LXF_PACKET_HEADER_SIZE], header_data[LXF_HEADER_DATA_SIZE];
> + int ret;
> + AVStream *st;
> + uint32_t format, video_params, disk_params;
> + uint16_t record_date, expiration_date;
> +
> + if ((ret = get_packet_header(s, header, &format)) < 0)
> + return ret;
> +
> + if (ret != LXF_HEADER_DATA_SIZE) {
> + av_log(s, AV_LOG_ERROR, "expected %d B size header, got %d\n",
> + LXF_HEADER_DATA_SIZE, ret);
> + return -1;
AVERROR_INVALIDDATA
> + }
> +
> + if (get_buffer(pb, header_data, LXF_HEADER_DATA_SIZE) != LXF_HEADER_DATA_SIZE)
> + return AVERROR_IO;
> +
> + if (!(st = av_new_stream(s, 0)))
> + return AVERROR_NOMEM;
> +
> + st->duration = AV_RL32(&header_data[32]);
> + video_params = AV_RL32(&header_data[40]);
> + record_date = AV_RL16(&header_data[56]);
> + expiration_date = AV_RL16(&header_data[58]);
> + disk_params = AV_RL32(&header_data[116]);
> +
> + st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
> + st->codec->bit_rate = 1000000 * ((video_params >> 14) & 0xFF);
> + st->codec->codec_tag = video_params & 0xF;
> + st->codec->codec_id = ff_codec_get_id(lxf_tags, st->codec->codec_tag);
> +
> + av_log(s, AV_LOG_DEBUG, "record: %x = %i-%02i-%02i\n",
> + record_date, 1900 + (record_date & 0x7F), (record_date >> 7) & 0xF,
> + (record_date >> 11) & 0x1F);
> +
> + av_log(s, AV_LOG_DEBUG, "expire: %x = %i-%02i-%02i\n",
> + expiration_date, 1900 + (expiration_date & 0x7F), (expiration_date >> 7) & 0xF,
> + (expiration_date >> 11) & 0x1F);
> +
> + if ((video_params >> 22) & 1)
> + av_log(s, AV_LOG_WARNING, "VBI data not yet supported\n");
> +
> + if ((lxf->channels = (disk_params >> 2) & 0xF)) {
> + if (!(st = av_new_stream(s, 1)))
> + return AVERROR_NOMEM;
> +
> + st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
> + st->codec->sample_rate = LXF_SAMPLERATE;
> + st->codec->channels = lxf->channels;
> +
> + av_set_pts_info(st, 64, 1, st->codec->sample_rate);
> + }
> +
> + if (format == 1) {
> + //skip extended field data
> + url_fskip(s->pb, (uint32_t)AV_RL32(&header[40]));
> + }
> +
> + return 0;
> +}
> +
> +/**
> + * De-planerize the PCM data in lxf->temp
> + * FIXME: remove this once support for planar audio is added to libavcodec
> + *
> + * @param[out] out where to write the de-planerized data to
> + * @param[in] bytes the total size of the PCM data
> + */
> +static void deplanarize(LXFDemuxContext *lxf, AVStream *ast, uint8_t *out, int bytes)
> +{
> + int x, y, z, i, bytes_per_sample = ast->codec->bits_per_coded_sample >> 3;
> +
> + for (z = i = 0; z < lxf->channels; z++)
> + for (y = 0; y < bytes / bytes_per_sample / lxf->channels; y++)
> + for (x = 0; x < bytes_per_sample; x++, i++)
> + out[x + bytes_per_sample*(z + y*lxf->channels)] = lxf->temp[i];
> +}
> +
> +static int lxf_read_packet(AVFormatContext *s, AVPacket *pkt)
> +{
> + LXFDemuxContext *lxf = s->priv_data;
> + ByteIOContext *pb = s->pb;
> + uint8_t header[LXF_PACKET_HEADER_SIZE], *buf;
> + AVStream *ast = NULL;
> + uint32_t stream, format;
> + int ret;
> +
> + if ((ret = get_packet_header(s, header, &format)) < 0)
> + return ret;
> +
> + stream = AV_RL32(&header[16]);
> +
> + if (stream > 1) {
> + av_log(s, AV_LOG_WARNING, "got packet with illegal stream index %u\n", stream);
> + return AVERROR(EAGAIN);
> + }
> +
> + if (stream == 1 && !(ast = s->streams[1])) {
> + av_log(s, AV_LOG_ERROR, "got audio packet without having an audio stream\n");
> + return -1;
> + }
AVERROR_INVALIDDATA
> +
> + //make sure the data fits in the de-planerization buffer
> + if (ast && ret > LXF_MAX_AUDIO_PACKET) {
> + av_log(s, AV_LOG_ERROR, "audio packet too large (%i > %i)\n",
> + ret, LXF_MAX_AUDIO_PACKET);
> + return -1;
> + }
ditto
> + if (av_new_packet(pkt, ret))
> + return AVERROR_IO;
maybe you can propagate the error given by av_new_packet()
> +
> + //read non-20-bit audio data into lxf->temp so we can deplanarize it
> + buf = ast && ast->codec->codec_id != CODEC_ID_PCM_LXF ? lxf->temp : pkt->data;
> +
> + if (get_buffer(pb, buf, ret) != ret) {
> + av_free_packet(pkt);
> + return AVERROR_IO;
> + }
> +
> + pkt->stream_index = stream;
> +
> + if (ast) {
> + if(ast->codec->codec_id != CODEC_ID_PCM_LXF)
> + deplanarize(lxf, ast, pkt->data, ret);
> + } else {
> + //picture type (0 = closed I, 1 = open I, 2 = P, 3 = B)
> + if (((format >> 22) & 0x3) < 2)
> + pkt->flags |= AV_PKT_FLAG_KEY;
> +
> + pkt->dts = lxf->frame_number++;
> + }
> +
> + return ret;
> +}
> +
> +AVInputFormat lxf_demuxer = {
> + "lxf",
> + NULL_IF_CONFIG_SMALL("VR native stream format (LXF)"),
> + sizeof(LXFDemuxContext),
> + lxf_probe,
> + lxf_read_header,
> + lxf_read_packet,
> + .codec_tag = (const AVCodecTag* const []){lxf_tags, 0},
> +};
possibly use designated init, more readable and doesn't break when we
break ABI
Regards.
--
FFmpeg = Foolish and Frightening Mastodontic Pacific Extravagant Ghost
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