Re: [FFmpeg-devel] [PATCH 8/8] ffmdec: don't seek back at EOF

2015-03-09 Thread Michael Niedermayer 
On Mon, Mar 09, 2015 at 12:27:15PM +0100, Andreas Cadhalpun wrote:
 On 09.03.2015 03:46, Michael Niedermayer wrote:
 On Mon, Mar 09, 2015 at 12:05:31AM +0100, Andreas Cadhalpun wrote:
 Hi,
 
 I'm not sure what the purpose of this avio_seek was, but it can
 result in an endless loop. Maybe it always does.
 
 ffm files can be written to and read at the same time, they can act
 as ring buffers so that data is written till the end and then
 continues at the begin
 i suspect this patch breaks that
 
 But if the file is not used as a ring buffer, it shouldn't play endlessly.

yes


 Maybe one should add a check that the data at the beginning is
 actually different than the last time?

maybe reynaldo can comment on how to best detect the ring buffer use
i think it always involves ffserver currently unless iam missing
something. It would of course make sense to allow other applications
to use it too ...
maybe a simple AVOption flag could be used to enable it, not sure

[...]

-- 
Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

I am the wisest man alive, for I know one thing, and that is that I know
nothing. -- Socrates


signature.asc
Description: Digital signature
___
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel

Re: [FFmpeg-devel] [PATCH 8/8] ffmdec: don't seek back at EOF

2015-03-08 Thread Michael Niedermayer 
On Mon, Mar 09, 2015 at 12:05:31AM +0100, Andreas Cadhalpun wrote:
 Hi,
 
 I'm not sure what the purpose of this avio_seek was, but it can
 result in an endless loop. Maybe it always does.

ffm files can be written to and read at the same time, they can act
as ring buffers so that data is written till the end and then
continues at the begin
i suspect this patch breaks that

[...]

-- 
Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

He who knows, does not speak. He who speaks, does not know. -- Lao Tsu


signature.asc
Description: Digital signature
___
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel

[FFmpeg-devel] [PATCH 8/8] ffmdec: don't seek back at EOF

2015-03-08 Thread Andreas Cadhalpun 

Hi,

I'm not sure what the purpose of this avio_seek was, but it can result 
in an endless loop. Maybe it always does.


Best regards,
Andreas
From e69589b1435b4d3e7a0a4de6158149f11a99a681 Mon Sep 17 00:00:00 2001
From: Andreas Cadhalpun andreas.cadhal...@googlemail.com
Date: Sun, 8 Mar 2015 23:39:23 +0100
Subject: [PATCH 8/8] ffmdec: don't seek back at EOF

Doing so can cause the ffm demuxer to return the same packets endlessly.

Signed-off-by: Andreas Cadhalpun andreas.cadhal...@googlemail.com
---
 libavformat/ffmdec.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavformat/ffmdec.c b/libavformat/ffmdec.c
index 9f00fc4..97849f8 100644
--- a/libavformat/ffmdec.c
+++ b/libavformat/ffmdec.c
@@ -91,7 +91,7 @@ static int ffm_read_data(AVFormatContext *s,
 len = size;
 if (len == 0) {
 if (avio_tell(pb) == ffm-file_size)
-avio_seek(pb, ffm-packet_size, SEEK_SET);
+return AVERROR_EOF;
 retry_read:
 if (pb-buffer_size != ffm-packet_size) {
 int64_t tell = avio_tell(pb);
-- 
2.1.4

___
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel