[FFmpeg-devel] [PATCH] lxfdec: support version 1 files, too.
Reimar Döffinger
Reimar.Doeffinger at gmx.de
Sat Mar 24 16:48:10 CET 2012
Fixes trac issue #656.
Signed-off-by: Reimar Döffinger <Reimar.Doeffinger at gmx.de>
---
libavformat/lxfdec.c | 92 ++++++++++++++++++++++++++++++++------------------
1 files changed, 59 insertions(+), 33 deletions(-)
diff --git a/libavformat/lxfdec.c b/libavformat/lxfdec.c
index f82d4f4..b6b6810 100644
--- a/libavformat/lxfdec.c
+++ b/libavformat/lxfdec.c
@@ -20,11 +20,12 @@
*/
#include "libavutil/intreadwrite.h"
+#include "libavcodec/bytestream.h"
#include "avformat.h"
#include "internal.h"
#include "riff.h"
-#define LXF_PACKET_HEADER_SIZE 60
+#define LXF_MAX_PACKET_HEADER_SIZE 256
#define LXF_HEADER_DATA_SIZE 120
#define LXF_IDENT "LEITCH\0"
#define LXF_IDENT_LENGTH 8
@@ -49,6 +50,7 @@ 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
+ uint32_t video_format, packet_type, extended_size;
} LXFDemuxContext;
static int lxf_probe(AVProbeData *p)
@@ -65,12 +67,12 @@ static int lxf_probe(AVProbeData *p)
* @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)
+static int check_checksum(const uint8_t *header, int size)
{
int x;
uint32_t sum = 0;
- for (x = 0; x < LXF_PACKET_HEADER_SIZE; x += 4)
+ for (x = 0; x < size; x += 4)
sum += AV_RL32(&header[x]);
return sum;
@@ -106,40 +108,60 @@ static int sync(AVFormatContext *s, uint8_t *header)
/**
* 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)
+static int get_packet_header(AVFormatContext *s)
{
+ LXFDemuxContext *lxf = s->priv_data;
AVIOContext *pb = s->pb;
int track_size, samples, ret;
+ uint32_t version, audio_format, header_size, channels, tmp;
AVStream *st;
+ uint8_t header[LXF_MAX_PACKET_HEADER_SIZE];
+ const uint8_t *p;
//find and read the ident
if ((ret = sync(s, header)) < 0)
return ret;
+ ret = avio_read(pb, header + LXF_IDENT_LENGTH, 8);
+ if (ret != 8)
+ return ret < 0 ? ret : AVERROR_EOF;
+
+ p = header + LXF_IDENT_LENGTH;
+ version = bytestream_get_le32(&p);
+ header_size = bytestream_get_le32(&p);
+ if (version > 1)
+ av_log_ask_for_sample(s, "Unknown format version %i\n", version);
+ if (header_size < (version ? 72 : 60) ||
+ header_size > LXF_MAX_PACKET_HEADER_SIZE ||
+ (header_size & 3)) {
+ av_log(s, AV_LOG_ERROR, "Invalid header size 0x%x\n", header_size);
+ return AVERROR_INVALIDDATA;
+ }
+
//read the rest of the packet header
- if ((ret = avio_read(pb, header + LXF_IDENT_LENGTH,
- LXF_PACKET_HEADER_SIZE - LXF_IDENT_LENGTH)) !=
- LXF_PACKET_HEADER_SIZE - LXF_IDENT_LENGTH) {
+ if ((ret = avio_read(pb, header + (p - header),
+ header_size - (p - header))) !=
+ header_size - (p - header)) {
return ret < 0 ? ret : AVERROR_EOF;
}
- if (check_checksum(header))
+ if (check_checksum(header, header_size))
av_log(s, AV_LOG_ERROR, "checksum error\n");
- *format = AV_RL32(&header[32]);
- ret = AV_RL32(&header[36]);
+ lxf->packet_type = bytestream_get_le32(&p);
+ p += version ? 20 : 12;
- //type
- switch (AV_RL32(&header[16])) {
+ lxf->extended_size = 0;
+ switch (lxf->packet_type) {
case 0:
//video
+ lxf->video_format = bytestream_get_le32(&p);
+ ret = bytestream_get_le32(&p);
//skip VBI data and metadata
- avio_skip(pb, (int64_t)(uint32_t)AV_RL32(&header[44]) +
- (int64_t)(uint32_t)AV_RL32(&header[52]));
+ avio_skip(pb, (int64_t)(uint32_t)AV_RL32(p + 4) +
+ (int64_t)(uint32_t)AV_RL32(p + 12));
break;
case 1:
//audio
@@ -148,12 +170,16 @@ static int get_packet_header(AVFormatContext *s, uint8_t *header, uint32_t *form
break;
}
+ if (version == 0) p += 8;
+ audio_format = bytestream_get_le32(&p);
+ channels = bytestream_get_le32(&p);
+ track_size = bytestream_get_le32(&p);
+
//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;
+ st->codec->bits_per_coded_sample = (audio_format >> 6) & 0x3F;
- if (st->codec->bits_per_coded_sample != (*format & 0x3F)) {
+ if (st->codec->bits_per_coded_sample != (audio_format & 0x3F)) {
av_log(s, AV_LOG_WARNING, "only tightly packed PCM currently supported\n");
return AVERROR_PATCHWELCOME;
}
@@ -169,7 +195,6 @@ static int get_packet_header(AVFormatContext *s, uint8_t *header, uint32_t *form
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
@@ -186,10 +211,14 @@ static int get_packet_header(AVFormatContext *s, uint8_t *header, uint32_t *form
}
//TODO: warning if track mask != (1 << channels) - 1?
- ret = av_popcount(AV_RL32(&header[44])) * track_size;
+ ret = av_popcount(channels) * track_size;
break;
default:
+ tmp = bytestream_get_le32(&p);
+ ret = bytestream_get_le32(&p);
+ if (tmp == 1)
+ lxf->extended_size = bytestream_get_le32(&p);
break;
}
@@ -200,13 +229,13 @@ static int lxf_read_header(AVFormatContext *s)
{
LXFDemuxContext *lxf = s->priv_data;
AVIOContext *pb = s->pb;
- uint8_t header[LXF_PACKET_HEADER_SIZE], header_data[LXF_HEADER_DATA_SIZE];
+ uint8_t header_data[LXF_HEADER_DATA_SIZE];
int ret;
AVStream *st;
- uint32_t format, video_params, disk_params;
+ uint32_t video_params, disk_params;
uint16_t record_date, expiration_date;
- if ((ret = get_packet_header(s, header, &format)) < 0)
+ if ((ret = get_packet_header(s)) < 0)
return ret;
if (ret != LXF_HEADER_DATA_SIZE) {
@@ -254,10 +283,7 @@ static int lxf_read_header(AVFormatContext *s)
avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
}
- if (format == 1) {
- //skip extended field data
- avio_skip(s->pb, (uint32_t)AV_RL32(&header[40]));
- }
+ avio_skip(s->pb, lxf->extended_size);
return 0;
}
@@ -283,15 +309,15 @@ static int lxf_read_packet(AVFormatContext *s, AVPacket *pkt)
{
LXFDemuxContext *lxf = s->priv_data;
AVIOContext *pb = s->pb;
- uint8_t header[LXF_PACKET_HEADER_SIZE], *buf;
+ uint8_t *buf;
AVStream *ast = NULL;
- uint32_t stream, format;
+ uint32_t stream;
int ret, ret2;
- if ((ret = get_packet_header(s, header, &format)) < 0)
+ if ((ret = get_packet_header(s)) < 0)
return ret;
- stream = AV_RL32(&header[16]);
+ stream = lxf->packet_type;
if (stream > 1) {
av_log(s, AV_LOG_WARNING, "got packet with illegal stream index %u\n", stream);
@@ -328,7 +354,7 @@ static int lxf_read_packet(AVFormatContext *s, AVPacket *pkt)
deplanarize(lxf, ast, pkt->data, ret);
} else {
//picture type (0 = closed I, 1 = open I, 2 = P, 3 = B)
- if (((format >> 22) & 0x3) < 2)
+ if (((lxf->video_format >> 22) & 0x3) < 2)
pkt->flags |= AV_PKT_FLAG_KEY;
pkt->dts = lxf->frame_number++;
--
1.7.9.1
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