Re: [FFmpeg-devel] [PATCH] yuv4mpeg: add rough duration estimate and seeking.
Dana 11. 7. 2015. 03:16 osoba Ronald S. Bultje rsbul...@gmail.com
napisala je:
---
libavformat/yuv4mpeg.h | 1 +
libavformat/yuv4mpegdec.c| 26 +++
tests/ref/seek/lavf-yuv4mpeg | 78
+---
3 files changed, 72 insertions(+), 33 deletions(-)
diff --git a/libavformat/yuv4mpeg.h b/libavformat/yuv4mpeg.h
index 750f498..eba7337 100644
--- a/libavformat/yuv4mpeg.h
+++ b/libavformat/yuv4mpeg.h
@@ -23,5 +23,6 @@
#define Y4M_MAGIC YUV4MPEG2
#define Y4M_FRAME_MAGIC FRAME
+#define Y4M_FRAME_MAGIC_LEN 6
#endif /* AVFORMAT_YUV4MPEG_H */
diff --git a/libavformat/yuv4mpegdec.c b/libavformat/yuv4mpegdec.c
index 7613c3c..4ebdb78 100644
--- a/libavformat/yuv4mpegdec.c
+++ b/libavformat/yuv4mpegdec.c
@@ -256,6 +256,12 @@ static int yuv4_read_header(AVFormatContext *s)
st-sample_aspect_ratio = (AVRational){ aspectn, aspectd };
st-codec-chroma_sample_location = chroma_sample_location;
st-codec-field_order= field_order;
+s-packet_size = avpicture_get_size(st-codec-pix_fmt, width,
height) + Y4M_FRAME_MAGIC_LEN;
+if ((int) s-packet_size 0)
+return s-packet_size;
+s-internal-data_offset = avio_tell(pb);
+
+st-duration = (avio_size(pb) - avio_tell(pb)) / s-packet_size;
return 0;
}
@@ -264,7 +270,7 @@ static int yuv4_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
int i;
char header[MAX_FRAME_HEADER+1];
-int packet_size, width, height, ret;
+int width, height, ret, off = avio_tell(s-pb);
AVStream *st = s-streams[0];
for (i = 0; i MAX_FRAME_HEADER; i++) {
@@ -287,17 +293,22 @@ static int yuv4_read_packet(AVFormatContext *s,
AVPacket *pkt)
width = st-codec-width;
height = st-codec-height;
-packet_size = avpicture_get_size(st-codec-pix_fmt, width, height);
-if (packet_size 0)
-return packet_size;
-
-ret = av_get_packet(s-pb, pkt, packet_size);
+ret = av_get_packet(s-pb, pkt, s-packet_size -
Y4M_FRAME_MAGIC_LEN);
if (ret 0)
return ret;
-else if (ret != packet_size)
+else if (ret != s-packet_size - Y4M_FRAME_MAGIC_LEN)
return s-pb-eof_reached ? AVERROR_EOF : AVERROR(EIO);
pkt-stream_index = 0;
+pkt-pts = (off - s-internal-data_offset) / s-packet_size;
+pkt-duration = 1;
+return 0;
+}
+
+static int yuv4_read_seek(AVFormatContext *s, int stream_index,
+ int64_t pts, int flags)
+{
+avio_seek(s-pb, pts * s-packet_size + s-internal-data_offset,
SEEK_SET);
return 0;
}
@@ -316,5 +327,6 @@ AVInputFormat ff_yuv4mpegpipe_demuxer = {
.read_probe = yuv4_probe,
.read_header= yuv4_read_header,
.read_packet= yuv4_read_packet,
+.read_seek = yuv4_read_seek,
.extensions = y4m,
};
diff --git a/tests/ref/seek/lavf-yuv4mpeg b/tests/ref/seek/lavf-yuv4mpeg
index 81c1de9..60c3036 100644
--- a/tests/ref/seek/lavf-yuv4mpeg
+++ b/tests/ref/seek/lavf-yuv4mpeg
@@ -1,27 +1,53 @@
ret: 0 st: 0 flags:1 dts: 0.00 pts: 0.00 pos: 64
size:152064
-ret:-1 st:-1 flags:0 ts:-1.00
-ret:-1 st:-1 flags:1 ts: 1.894167
-ret:-1 st: 0 flags:0 ts: 0.80
-ret:-1 st: 0 flags:1 ts:-0.32
-ret:-1 st:-1 flags:0 ts: 2.576668
-ret:-1 st:-1 flags:1 ts: 1.470835
-ret:-1 st: 0 flags:0 ts: 0.36
-ret:-1 st: 0 flags:1 ts:-0.76
-ret:-1 st:-1 flags:0 ts: 2.153336
-ret:-1 st:-1 flags:1 ts: 1.047503
-ret:-1 st: 0 flags:0 ts:-0.04
-ret:-1 st: 0 flags:1 ts: 2.84
-ret:-1 st:-1 flags:0 ts: 1.730004
-ret:-1 st:-1 flags:1 ts: 0.624171
-ret:-1 st: 0 flags:0 ts:-0.48
-ret:-1 st: 0 flags:1 ts: 2.40
-ret:-1 st:-1 flags:0 ts: 1.306672
-ret:-1 st:-1 flags:1 ts: 0.200839
-ret:-1 st: 0 flags:0 ts:-0.92
-ret:-1 st: 0 flags:1 ts: 2.00
-ret:-1 st:-1 flags:0 ts: 0.883340
-ret:-1 st:-1 flags:1 ts:-0.222493
-ret:-1 st: 0 flags:0 ts: 2.68
-ret:-1 st: 0 flags:1 ts: 1.56
-ret:-1 st:-1 flags:0 ts: 0.460008
-ret:-1 st:-1 flags:1 ts:-0.645825
+ret: 0 st:-1 flags:0 ts:-1.00
+ret: 0 st: 0 flags:1 dts: 0.04 pts: 0.04 pos: 152134
size:152064
+ret: 0 st:-1 flags:1 ts: 1.894167
+ret:-EOF
+ret: 0 st: 0 flags:0 ts: 0.80
+ret: 0 st: 0 flags:1 dts: 0.80 pts: 0.80 pos:3041464
size:152064
+ret: 0 st: 0 flags:1 ts:-0.32
+ret: 0 st: 0 flags:1 dts: 0.84 pts: 0.84 pos:3193534
size:152064
+ret: 0 st:-1 flags:0 ts: 2.576668
+ret:-EOF
+ret: 0 st:-1 flags:1 ts: 1.470835
+ret:-EOF
+ret: 0 st: 0 flags:0 ts: 0.36
+ret: 0 st: 0 flags:1 dts: 0.36 pts: 0.36
Re: [FFmpeg-devel] [PATCH] yuv4mpeg: add rough duration estimate and seeking.
On Sat, Jul 11, 2015 at 10:59:58AM +, Paul B Mahol wrote:
Dana 11. 7. 2015. 03:16 osoba Ronald S. Bultje rsbul...@gmail.com
napisala je:
---
libavformat/yuv4mpeg.h | 1 +
libavformat/yuv4mpegdec.c| 26 +++
tests/ref/seek/lavf-yuv4mpeg | 78
+---
3 files changed, 72 insertions(+), 33 deletions(-)
diff --git a/libavformat/yuv4mpeg.h b/libavformat/yuv4mpeg.h
index 750f498..eba7337 100644
--- a/libavformat/yuv4mpeg.h
+++ b/libavformat/yuv4mpeg.h
@@ -23,5 +23,6 @@
#define Y4M_MAGIC YUV4MPEG2
#define Y4M_FRAME_MAGIC FRAME
+#define Y4M_FRAME_MAGIC_LEN 6
#endif /* AVFORMAT_YUV4MPEG_H */
diff --git a/libavformat/yuv4mpegdec.c b/libavformat/yuv4mpegdec.c
index 7613c3c..4ebdb78 100644
--- a/libavformat/yuv4mpegdec.c
+++ b/libavformat/yuv4mpegdec.c
@@ -256,6 +256,12 @@ static int yuv4_read_header(AVFormatContext *s)
st-sample_aspect_ratio = (AVRational){ aspectn, aspectd };
st-codec-chroma_sample_location = chroma_sample_location;
st-codec-field_order= field_order;
+s-packet_size = avpicture_get_size(st-codec-pix_fmt, width,
height) + Y4M_FRAME_MAGIC_LEN;
+if ((int) s-packet_size 0)
+return s-packet_size;
+s-internal-data_offset = avio_tell(pb);
+
+st-duration = (avio_size(pb) - avio_tell(pb)) / s-packet_size;
return 0;
}
@@ -264,7 +270,7 @@ static int yuv4_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
int i;
char header[MAX_FRAME_HEADER+1];
-int packet_size, width, height, ret;
+int width, height, ret, off = avio_tell(s-pb);
AVStream *st = s-streams[0];
for (i = 0; i MAX_FRAME_HEADER; i++) {
@@ -287,17 +293,22 @@ static int yuv4_read_packet(AVFormatContext *s,
AVPacket *pkt)
width = st-codec-width;
height = st-codec-height;
-packet_size = avpicture_get_size(st-codec-pix_fmt, width, height);
-if (packet_size 0)
-return packet_size;
-
-ret = av_get_packet(s-pb, pkt, packet_size);
+ret = av_get_packet(s-pb, pkt, s-packet_size -
Y4M_FRAME_MAGIC_LEN);
if (ret 0)
return ret;
-else if (ret != packet_size)
+else if (ret != s-packet_size - Y4M_FRAME_MAGIC_LEN)
return s-pb-eof_reached ? AVERROR_EOF : AVERROR(EIO);
pkt-stream_index = 0;
+pkt-pts = (off - s-internal-data_offset) / s-packet_size;
+pkt-duration = 1;
+return 0;
+}
+
+static int yuv4_read_seek(AVFormatContext *s, int stream_index,
+ int64_t pts, int flags)
+{
+avio_seek(s-pb, pts * s-packet_size + s-internal-data_offset,
SEEK_SET);
return 0;
}
@@ -316,5 +327,6 @@ AVInputFormat ff_yuv4mpegpipe_demuxer = {
.read_probe = yuv4_probe,
.read_header= yuv4_read_header,
.read_packet= yuv4_read_packet,
+.read_seek = yuv4_read_seek,
.extensions = y4m,
};
diff --git a/tests/ref/seek/lavf-yuv4mpeg b/tests/ref/seek/lavf-yuv4mpeg
index 81c1de9..60c3036 100644
--- a/tests/ref/seek/lavf-yuv4mpeg
+++ b/tests/ref/seek/lavf-yuv4mpeg
@@ -1,27 +1,53 @@
ret: 0 st: 0 flags:1 dts: 0.00 pts: 0.00 pos: 64
size:152064
-ret:-1 st:-1 flags:0 ts:-1.00
-ret:-1 st:-1 flags:1 ts: 1.894167
-ret:-1 st: 0 flags:0 ts: 0.80
-ret:-1 st: 0 flags:1 ts:-0.32
-ret:-1 st:-1 flags:0 ts: 2.576668
-ret:-1 st:-1 flags:1 ts: 1.470835
-ret:-1 st: 0 flags:0 ts: 0.36
-ret:-1 st: 0 flags:1 ts:-0.76
-ret:-1 st:-1 flags:0 ts: 2.153336
-ret:-1 st:-1 flags:1 ts: 1.047503
-ret:-1 st: 0 flags:0 ts:-0.04
-ret:-1 st: 0 flags:1 ts: 2.84
-ret:-1 st:-1 flags:0 ts: 1.730004
-ret:-1 st:-1 flags:1 ts: 0.624171
-ret:-1 st: 0 flags:0 ts:-0.48
-ret:-1 st: 0 flags:1 ts: 2.40
-ret:-1 st:-1 flags:0 ts: 1.306672
-ret:-1 st:-1 flags:1 ts: 0.200839
-ret:-1 st: 0 flags:0 ts:-0.92
-ret:-1 st: 0 flags:1 ts: 2.00
-ret:-1 st:-1 flags:0 ts: 0.883340
-ret:-1 st:-1 flags:1 ts:-0.222493
-ret:-1 st: 0 flags:0 ts: 2.68
-ret:-1 st: 0 flags:1 ts: 1.56
-ret:-1 st:-1 flags:0 ts: 0.460008
-ret:-1 st:-1 flags:1 ts:-0.645825
+ret: 0 st:-1 flags:0 ts:-1.00
+ret: 0 st: 0 flags:1 dts: 0.04 pts: 0.04 pos: 152134
size:152064
+ret: 0 st:-1 flags:1 ts: 1.894167
+ret:-EOF
+ret: 0 st: 0 flags:0 ts: 0.80
+ret: 0 st: 0 flags:1 dts: 0.80 pts: 0.80 pos:3041464
size:152064
+ret: 0 st: 0 flags:1 ts:-0.32
+ret: 0 st: 0 flags:1 dts: 0.84 pts: 0.84 pos:3193534
size:152064
+ret: 0 st:-1
Re: [FFmpeg-devel] [PATCH] yuv4mpeg: add rough duration estimate and seeking.
On Mon, Jun 22, 2015 at 11:02 AM, wm4 nfx...@googlemail.com wrote: On Sun, 21 Jun 2015 18:34:33 -0400 Ronald S. Bultje rsbul...@gmail.com wrote: Hi, On Sun, Jun 21, 2015 at 5:17 PM, Hendrik Leppkes h.lepp...@gmail.com wrote: On Sun, Jun 21, 2015 at 10:41 PM, Ronald S. Bultje rsbul...@gmail.com wrote: --- libavformat/yuv4mpeg.h| 1 + libavformat/yuv4mpegdec.c | 26 +++--- 2 files changed, 20 insertions(+), 7 deletions(-) What happens if a seek does not end up on a perfect frame boundary? Wouldn't that entirely screw over any further reading? So is it really that rough, or does it actually work precise enough to do that? It works for all y4m files I see in the wild, but the problem is that the y4m spec is a little confusing. The frame header magic is FRAME, followed by optional per-frame options, and then a \n. This is always empty (i.e. FRAME\n), but in theory it could be non-empty and then this doesn't work. I don't know how much we care about such theoretical files to make a more difficult dur/seek implementation. Why not use generic seeking mode? Add AVFMT_GENERIC_INDEX to the format flags. The utils.c will do seeking by doing byte seeks and using the byte position of previous packets. If you seek forward, it will read and skip packets until the target is reached (for parts of the file that have not been indexed yet). This should be very reliable, but of course seek speed will depend on I/O bandwidth. Generic seeking is rather expensive, and if a format is already strict CBR, doing a seek based on that is probably better. I wonder how hard it would be to write a re-sync function to find the next FRAME header when a seek does actually end up on the wrong spot. - Hendrik ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [PATCH] yuv4mpeg: add rough duration estimate and seeking.
On Sun, 21 Jun 2015 18:34:33 -0400 Ronald S. Bultje rsbul...@gmail.com wrote: Hi, On Sun, Jun 21, 2015 at 5:17 PM, Hendrik Leppkes h.lepp...@gmail.com wrote: On Sun, Jun 21, 2015 at 10:41 PM, Ronald S. Bultje rsbul...@gmail.com wrote: --- libavformat/yuv4mpeg.h| 1 + libavformat/yuv4mpegdec.c | 26 +++--- 2 files changed, 20 insertions(+), 7 deletions(-) What happens if a seek does not end up on a perfect frame boundary? Wouldn't that entirely screw over any further reading? So is it really that rough, or does it actually work precise enough to do that? It works for all y4m files I see in the wild, but the problem is that the y4m spec is a little confusing. The frame header magic is FRAME, followed by optional per-frame options, and then a \n. This is always empty (i.e. FRAME\n), but in theory it could be non-empty and then this doesn't work. I don't know how much we care about such theoretical files to make a more difficult dur/seek implementation. Why not use generic seeking mode? Add AVFMT_GENERIC_INDEX to the format flags. The utils.c will do seeking by doing byte seeks and using the byte position of previous packets. If you seek forward, it will read and skip packets until the target is reached (for parts of the file that have not been indexed yet). This should be very reliable, but of course seek speed will depend on I/O bandwidth. ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [PATCH] yuv4mpeg: add rough duration estimate and seeking.
On Mon, 22 Jun 2015 11:23:55 +0200 Hendrik Leppkes h.lepp...@gmail.com wrote: On Mon, Jun 22, 2015 at 11:02 AM, wm4 nfx...@googlemail.com wrote: On Sun, 21 Jun 2015 18:34:33 -0400 Ronald S. Bultje rsbul...@gmail.com wrote: Hi, On Sun, Jun 21, 2015 at 5:17 PM, Hendrik Leppkes h.lepp...@gmail.com wrote: On Sun, Jun 21, 2015 at 10:41 PM, Ronald S. Bultje rsbul...@gmail.com wrote: --- libavformat/yuv4mpeg.h| 1 + libavformat/yuv4mpegdec.c | 26 +++--- 2 files changed, 20 insertions(+), 7 deletions(-) What happens if a seek does not end up on a perfect frame boundary? Wouldn't that entirely screw over any further reading? So is it really that rough, or does it actually work precise enough to do that? It works for all y4m files I see in the wild, but the problem is that the y4m spec is a little confusing. The frame header magic is FRAME, followed by optional per-frame options, and then a \n. This is always empty (i.e. FRAME\n), but in theory it could be non-empty and then this doesn't work. I don't know how much we care about such theoretical files to make a more difficult dur/seek implementation. Why not use generic seeking mode? Add AVFMT_GENERIC_INDEX to the format flags. The utils.c will do seeking by doing byte seeks and using the byte position of previous packets. If you seek forward, it will read and skip packets until the target is reached (for parts of the file that have not been indexed yet). This should be very reliable, but of course seek speed will depend on I/O bandwidth. Generic seeking is rather expensive, and if a format is already strict CBR, doing a seek based on that is probably better. I wonder how hard it would be to write a re-sync function to find the next FRAME header when a seek does actually end up on the wrong spot. OK, but I'd rather have slow seeking than possibly randomly inaccurate seeking. Maybe the seek mode could be switched on AVFMT_FLAG_FAST_SEEK. ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [PATCH] yuv4mpeg: add rough duration estimate and seeking.
On Mon, 22 Jun 2015 07:52:21 -0400 Ronald S. Bultje rsbul...@gmail.com wrote: Hi, On Mon, Jun 22, 2015 at 6:24 AM, wm4 nfx...@googlemail.com wrote: On Mon, 22 Jun 2015 11:23:55 +0200 Hendrik Leppkes h.lepp...@gmail.com wrote: On Mon, Jun 22, 2015 at 11:02 AM, wm4 nfx...@googlemail.com wrote: On Sun, 21 Jun 2015 18:34:33 -0400 Ronald S. Bultje rsbul...@gmail.com wrote: Hi, On Sun, Jun 21, 2015 at 5:17 PM, Hendrik Leppkes h.lepp...@gmail.com wrote: On Sun, Jun 21, 2015 at 10:41 PM, Ronald S. Bultje rsbul...@gmail.com wrote: --- libavformat/yuv4mpeg.h| 1 + libavformat/yuv4mpegdec.c | 26 +++--- 2 files changed, 20 insertions(+), 7 deletions(-) What happens if a seek does not end up on a perfect frame boundary? Wouldn't that entirely screw over any further reading? So is it really that rough, or does it actually work precise enough to do that? It works for all y4m files I see in the wild, but the problem is that the y4m spec is a little confusing. The frame header magic is FRAME, followed by optional per-frame options, and then a \n. This is always empty (i.e. FRAME\n), but in theory it could be non-empty and then this doesn't work. I don't know how much we care about such theoretical files to make a more difficult dur/seek implementation. Why not use generic seeking mode? Add AVFMT_GENERIC_INDEX to the format flags. The utils.c will do seeking by doing byte seeks and using the byte position of previous packets. If you seek forward, it will read and skip packets until the target is reached (for parts of the file that have not been indexed yet). This should be very reliable, but of course seek speed will depend on I/O bandwidth. Generic seeking is rather expensive, and if a format is already strict CBR, doing a seek based on that is probably better. I wonder how hard it would be to write a re-sync function to find the next FRAME header when a seek does actually end up on the wrong spot. OK, but I'd rather have slow seeking than possibly randomly inaccurate seeking. Maybe the seek mode could be switched on AVFMT_FLAG_FAST_SEEK. Why don't we do that once we start seeing files with frame-headers other than empty FRAME\n in the wild? Right now they are just theoretical... I don't mind. If this happens, it'd be extremely visible anyway, because the pixels won't line up. ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [PATCH] yuv4mpeg: add rough duration estimate and seeking.
Ronald S. Bultje rsbultje at gmail.com writes: Why don't we do that once we start seeing files with frame-headers other than empty FRAME\n in the wild? +1 Carl Eugen ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [PATCH] yuv4mpeg: add rough duration estimate and seeking.
Le quartidi 4 messidor, an CCXXIII, Carl Eugen Hoyos a écrit : Why don't we do that once we start seeing files with frame-headers other than empty FRAME\n in the wild? +1 Me2. And do not forget that, technically, 0x46 0x52 0x41 0x4d 0x45 0x0a can very well appear in the frame data; with the bytes values, is is not even that unlikely. Generic seeking can only really work when the start code is guaranteed not to appear in the packets payload. Regards, -- Nicolas George signature.asc Description: Digital signature ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
[FFmpeg-devel] [PATCH] yuv4mpeg: add rough duration estimate and seeking.
---
libavformat/yuv4mpeg.h| 1 +
libavformat/yuv4mpegdec.c | 26 +++---
2 files changed, 20 insertions(+), 7 deletions(-)
diff --git a/libavformat/yuv4mpeg.h b/libavformat/yuv4mpeg.h
index 750f498..eba7337 100644
--- a/libavformat/yuv4mpeg.h
+++ b/libavformat/yuv4mpeg.h
@@ -23,5 +23,6 @@
#define Y4M_MAGIC YUV4MPEG2
#define Y4M_FRAME_MAGIC FRAME
+#define Y4M_FRAME_MAGIC_LEN 6
#endif /* AVFORMAT_YUV4MPEG_H */
diff --git a/libavformat/yuv4mpegdec.c b/libavformat/yuv4mpegdec.c
index 7613c3c..4ebdb78 100644
--- a/libavformat/yuv4mpegdec.c
+++ b/libavformat/yuv4mpegdec.c
@@ -256,6 +256,12 @@ static int yuv4_read_header(AVFormatContext *s)
st-sample_aspect_ratio = (AVRational){ aspectn, aspectd };
st-codec-chroma_sample_location = chroma_sample_location;
st-codec-field_order= field_order;
+s-packet_size = avpicture_get_size(st-codec-pix_fmt, width, height) +
Y4M_FRAME_MAGIC_LEN;
+if ((int) s-packet_size 0)
+return s-packet_size;
+s-internal-data_offset = avio_tell(pb);
+
+st-duration = (avio_size(pb) - avio_tell(pb)) / s-packet_size;
return 0;
}
@@ -264,7 +270,7 @@ static int yuv4_read_packet(AVFormatContext *s, AVPacket
*pkt)
{
int i;
char header[MAX_FRAME_HEADER+1];
-int packet_size, width, height, ret;
+int width, height, ret, off = avio_tell(s-pb);
AVStream *st = s-streams[0];
for (i = 0; i MAX_FRAME_HEADER; i++) {
@@ -287,17 +293,22 @@ static int yuv4_read_packet(AVFormatContext *s, AVPacket
*pkt)
width = st-codec-width;
height = st-codec-height;
-packet_size = avpicture_get_size(st-codec-pix_fmt, width, height);
-if (packet_size 0)
-return packet_size;
-
-ret = av_get_packet(s-pb, pkt, packet_size);
+ret = av_get_packet(s-pb, pkt, s-packet_size - Y4M_FRAME_MAGIC_LEN);
if (ret 0)
return ret;
-else if (ret != packet_size)
+else if (ret != s-packet_size - Y4M_FRAME_MAGIC_LEN)
return s-pb-eof_reached ? AVERROR_EOF : AVERROR(EIO);
pkt-stream_index = 0;
+pkt-pts = (off - s-internal-data_offset) / s-packet_size;
+pkt-duration = 1;
+return 0;
+}
+
+static int yuv4_read_seek(AVFormatContext *s, int stream_index,
+ int64_t pts, int flags)
+{
+avio_seek(s-pb, pts * s-packet_size + s-internal-data_offset,
SEEK_SET);
return 0;
}
@@ -316,5 +327,6 @@ AVInputFormat ff_yuv4mpegpipe_demuxer = {
.read_probe = yuv4_probe,
.read_header= yuv4_read_header,
.read_packet= yuv4_read_packet,
+.read_seek = yuv4_read_seek,
.extensions = y4m,
};
--
2.1.2
___
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [PATCH] yuv4mpeg: add rough duration estimate and seeking.
On Sun, Jun 21, 2015 at 10:41 PM, Ronald S. Bultje rsbul...@gmail.com wrote: --- libavformat/yuv4mpeg.h| 1 + libavformat/yuv4mpegdec.c | 26 +++--- 2 files changed, 20 insertions(+), 7 deletions(-) What happens if a seek does not end up on a perfect frame boundary? Wouldn't that entirely screw over any further reading? So is it really that rough, or does it actually work precise enough to do that? - Hendrik ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [PATCH] yuv4mpeg: add rough duration estimate and seeking.
Hi, On Sun, Jun 21, 2015 at 5:17 PM, Hendrik Leppkes h.lepp...@gmail.com wrote: On Sun, Jun 21, 2015 at 10:41 PM, Ronald S. Bultje rsbul...@gmail.com wrote: --- libavformat/yuv4mpeg.h| 1 + libavformat/yuv4mpegdec.c | 26 +++--- 2 files changed, 20 insertions(+), 7 deletions(-) What happens if a seek does not end up on a perfect frame boundary? Wouldn't that entirely screw over any further reading? So is it really that rough, or does it actually work precise enough to do that? It works for all y4m files I see in the wild, but the problem is that the y4m spec is a little confusing. The frame header magic is FRAME, followed by optional per-frame options, and then a \n. This is always empty (i.e. FRAME\n), but in theory it could be non-empty and then this doesn't work. I don't know how much we care about such theoretical files to make a more difficult dur/seek implementation. Ronald ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [PATCH] yuv4mpeg: add rough duration estimate and seeking.
On Sun, Jun 21, 2015 at 04:41:23PM -0400, Ronald S. Bultje wrote: --- libavformat/yuv4mpeg.h| 1 + libavformat/yuv4mpegdec.c | 26 +++--- 2 files changed, 20 insertions(+), 7 deletions(-) this needs to update the reference checksum for fate-seek-lavf-yuv4mpeg assuming the change is intended --- ./tests/ref/seek/lavf-yuv4mpeg 2015-06-20 16:32:37.183978941 +0200 +++ tests/data/fate/seek-lavf-yuv4mpeg 2015-06-22 00:38:43.982413616 +0200 @@ -1,27 +1,53 @@ ret: 0 st: 0 flags:1 dts: 0.00 pts: 0.00 pos: 64 size:152064 -ret:-1 st:-1 flags:0 ts:-1.00 -ret:-1 st:-1 flags:1 ts: 1.894167 -ret:-1 st: 0 flags:0 ts: 0.80 -ret:-1 st: 0 flags:1 ts:-0.32 -ret:-1 st:-1 flags:0 ts: 2.576668 -ret:-1 st:-1 flags:1 ts: 1.470835 -ret:-1 st: 0 flags:0 ts: 0.36 -ret:-1 st: 0 flags:1 ts:-0.76 -ret:-1 st:-1 flags:0 ts: 2.153336 -ret:-1 st:-1 flags:1 ts: 1.047503 -ret:-1 st: 0 flags:0 ts:-0.04 -ret:-1 st: 0 flags:1 ts: 2.84 -ret:-1 st:-1 flags:0 ts: 1.730004 -ret:-1 st:-1 flags:1 ts: 0.624171 -ret:-1 st: 0 flags:0 ts:-0.48 -ret:-1 st: 0 flags:1 ts: 2.40 -ret:-1 st:-1 flags:0 ts: 1.306672 -ret:-1 st:-1 flags:1 ts: 0.200839 -ret:-1 st: 0 flags:0 ts:-0.92 -ret:-1 st: 0 flags:1 ts: 2.00 -ret:-1 st:-1 flags:0 ts: 0.883340 -ret:-1 st:-1 flags:1 ts:-0.222493 -ret:-1 st: 0 flags:0 ts: 2.68 -ret:-1 st: 0 flags:1 ts: 1.56 -ret:-1 st:-1 flags:0 ts: 0.460008 -ret:-1 st:-1 flags:1 ts:-0.645825 +ret: 0 st:-1 flags:0 ts:-1.00 +ret: 0 st: 0 flags:1 dts: 0.04 pts: 0.04 pos: 152134 size:152064 +ret: 0 st:-1 flags:1 ts: 1.894167 +ret:-EOF +ret: 0 st: 0 flags:0 ts: 0.80 +ret: 0 st: 0 flags:1 dts: 0.80 pts: 0.80 pos:3041464 size:152064 +ret: 0 st: 0 flags:1 ts:-0.32 +ret: 0 st: 0 flags:1 dts: 0.84 pts: 0.84 pos:3193534 size:152064 +ret: 0 st:-1 flags:0 ts: 2.576668 +ret:-EOF +ret: 0 st:-1 flags:1 ts: 1.470835 +ret:-EOF +ret: 0 st: 0 flags:0 ts: 0.36 +ret: 0 st: 0 flags:1 dts: 0.36 pts: 0.36 pos:1368694 size:152064 +ret: 0 st: 0 flags:1 ts:-0.76 +ret: 0 st: 0 flags:1 dts: 0.40 pts: 0.40 pos:1520764 size:152064 +ret: 0 st:-1 flags:0 ts: 2.153336 +ret:-EOF +ret: 0 st:-1 flags:1 ts: 1.047503 +ret:-EOF +ret: 0 st: 0 flags:0 ts:-0.04 +ret:-EOF +ret: 0 st: 0 flags:1 ts: 2.84 +ret:-EOF +ret: 0 st:-1 flags:0 ts: 1.730004 +ret:-EOF +ret: 0 st:-1 flags:1 ts: 0.624171 +ret: 0 st: 0 flags:1 dts: 0.64 pts: 0.64 pos:2433184 size:152064 +ret: 0 st: 0 flags:0 ts:-0.48 +ret: 0 st: 0 flags:1 dts: 0.68 pts: 0.68 pos:2585254 size:152064 +ret: 0 st: 0 flags:1 ts: 2.40 +ret:-EOF +ret: 0 st:-1 flags:0 ts: 1.306672 +ret:-EOF +ret: 0 st:-1 flags:1 ts: 0.200839 +ret: 0 st: 0 flags:1 dts: 0.20 pts: 0.20 pos: 760414 size:152064 +ret: 0 st: 0 flags:0 ts:-0.92 +ret: 0 st: 0 flags:1 dts: 0.24 pts: 0.24 pos: 912484 size:152064 +ret: 0 st: 0 flags:1 ts: 2.00 +ret:-EOF +ret: 0 st:-1 flags:0 ts: 0.883340 +ret: 0 st: 0 flags:1 dts: 0.88 pts: 0.88 pos:3345604 size:152064 +ret: 0 st:-1 flags:1 ts:-0.222493 +ret: 0 st: 0 flags:1 dts: 0.92 pts: 0.92 pos:3497674 size:152064 +ret: 0 st: 0 flags:0 ts: 2.68 +ret:-EOF +ret: 0 st: 0 flags:1 ts: 1.56 +ret:-EOF +ret: 0 st:-1 flags:0 ts: 0.460008 +ret: 0 st: 0 flags:1 dts: 0.48 pts: 0.48 pos:1824904 size:152064 +ret: 0 st:-1 flags:1 ts:-0.645825 +ret: 0 st: 0 flags:1 dts: 0.52 pts: 0.52 pos:1976974 size:152064 Test seek-lavf-yuv4mpeg failed. Look at tests/data/fate/seek-lavf-yuv4mpeg.err for details. make: *** [fate-seek-lavf-yuv4mpeg] Error 1 make: *** Waiting for unfinished jobs [] -- Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB No snowflake in an avalanche ever feels responsible. -- Voltaire signature.asc Description: Digital signature ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
