Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

On Fri, Nov 3, 2017 at 12:38 AM, Derek Buitenhuis wrote: > On 11/2/2017 10:48 PM, Kieran Kunhya wrote: >> I have tried this using the following patch but it does not work: >> https://www.irccloud.com/pastebin/qobTcW9d/ >> >> Nothing obviously seems wrong so I suspect

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

On 11/2/2017 10:48 PM, Kieran Kunhya wrote: > I have tried this using the following patch but it does not work: > https://www.irccloud.com/pastebin/qobTcW9d/ > > Nothing obviously seems wrong so I suspect it's not possible to do this > whilst reusing the code between decoder and parser. > The old

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

> > The idea would be that there would only be one uint8_t buffer and the > 2000 entries from te pool would point into that. > So as a larger NAL shifts through the 2000 the pointers would get > distributed differently but the size would not grow > Any variable size buffer the H2645NAL needs would

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

On 11/1/2017 1:36 AM, Michael Niedermayer wrote: > The idea would be that there would only be one uint8_t buffer and the > 2000 entries from te pool would point into that. > So as a larger NAL shifts through the 2000 the pointers would get > distributed differently but the size would not grow >

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

On Tue, Oct 31, 2017 at 08:24:37PM +, Derek Buitenhuis wrote: > On 10/31/2017 2:25 AM, Michael Niedermayer wrote: > > (though as said, this fix is not ideal or complete, I would very much > > prefer if this would be fixed by using a single buffer or any other > > solution that avoids the

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

On Tue, 31 Oct 2017 at 22:36 Niki Bowe wrote: > I was going to prepare a patch, but it sounds like Kieran is going to. > Thank you Kieran. Let me know if there's anything you want me to do, or if > you would prefer me to do it for the experience. > > As for the

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

Thank you Kieran, Michael, Derek, and Carl. I ran some benchmarks and the patch I provided really does have a speed impact so I was considering alternative ways to achieve the same result. After a little thought last week I came to the same conclusion as Michael that a single rbsp_buffer per

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

> > Am I missing something here? > > P.S. I see Kieran mailed the same thing as I wrote this. > Further to Derek's excellent explanation, I think the best way is to go back to the old "in-place" NAL parsing code for H264. I will prepare a patch to do this. Kieran

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

On 10/31/2017 2:25 AM, Michael Niedermayer wrote: > (though as said, this fix is not ideal or complete, I would very much > prefer if this would be fixed by using a single buffer or any other > solution that avoids the speedloss.) Using a single buffer would be marginally faster, but it does

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

> > This reduces memory consumption to linear from qudratic but i think > it still can be made to allocate very large amounts of memory. > That is with many small NAL units MAX_MBPAIR_SIZE would be allocated > for each.in worst case. > So this does fix the qudratic issue but not the OOM issue. >

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

On Tue, 31 Oct 2017 at 02:26 Michael Niedermayer wrote: > On Thu, Oct 19, 2017 at 11:46:47AM -0700, Nikolas Bowe wrote: > > Found via fuzzing. > > /tmp/poc is a 1 MB mpegts file generated via fuzzing, where 1 packet has > many NALUs > > Before this change: > > $

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

On Thu, Oct 19, 2017 at 11:46:47AM -0700, Nikolas Bowe wrote: > Found via fuzzing. > /tmp/poc is a 1 MB mpegts file generated via fuzzing, where 1 packet has many > NALUs > Before this change: > $ /usr/bin/time -f "\t%M Max Resident Set Size (Kb)" ./ffprobe /tmp/poc > 2>&1 | tail -n 1 >

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

On Thu, Oct 19, 2017 at 11:46:47AM -0700, Nikolas Bowe wrote: > Found via fuzzing. > /tmp/poc is a 1 MB mpegts file generated via fuzzing, where 1 packet has many > NALUs > Before this change: > $ /usr/bin/time -f "\t%M Max Resident Set Size (Kb)" ./ffprobe /tmp/poc > 2>&1 | tail -n 1 >

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

Hi On Mon, Oct 23, 2017 at 04:43:55PM -0700, Niki Bowe wrote: > On Thu, Oct 19, 2017 at 3:39 PM, Carl Eugen Hoyos > wrote: > > > 2017-10-19 20:46 GMT+02:00 Nikolas Bowe : > > > Found via fuzzing. > > > /tmp/poc is a 1 MB mpegts file generated

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

On Tue, 31 Oct 2017 at 01:42 Kieran Kunhya wrote: > On Tue, 24 Oct 2017 at 00:56 Carl Eugen Hoyos wrote: > >> 2017-10-24 1:43 GMT+02:00 Niki Bowe : >> > On Thu, Oct 19, 2017 at 3:39 PM, Carl Eugen Hoyos >>

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

On Tue, 24 Oct 2017 at 00:56 Carl Eugen Hoyos wrote: > 2017-10-24 1:43 GMT+02:00 Niki Bowe : > > On Thu, Oct 19, 2017 at 3:39 PM, Carl Eugen Hoyos > > wrote: > > >> Does the patch have a measurable speed impact? > >> > > Is

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

2017-10-24 1:43 GMT+02:00 Niki Bowe : > On Thu, Oct 19, 2017 at 3:39 PM, Carl Eugen Hoyos > wrote: >> Does the patch have a measurable speed impact? >> > Is there a standard set of benchmarks I can run? > > For typical videos the speed impact

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

On Thu, Oct 19, 2017 at 3:39 PM, Carl Eugen Hoyos wrote: > 2017-10-19 20:46 GMT+02:00 Nikolas Bowe : > > Found via fuzzing. > > /tmp/poc is a 1 MB mpegts file generated via fuzzing, where 1 packet has > many NALUs > > Before this change: > >

Re: [FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

2017-10-19 20:46 GMT+02:00 Nikolas Bowe : > Found via fuzzing. > /tmp/poc is a 1 MB mpegts file generated via fuzzing, where 1 packet has many > NALUs > Before this change: > $ /usr/bin/time -f "\t%M Max Resident Set Size (Kb)" ./ffprobe /tmp/poc > 2>&1 | tail

[FFmpeg-devel] [PATCH] Fix quadratic memory use in ff_h2645_extract_rbsp() when multiple NALUs exist in packet.

Found via fuzzing. /tmp/poc is a 1 MB mpegts file generated via fuzzing, where 1 packet has many NALUs Before this change: $ /usr/bin/time -f "\t%M Max Resident Set Size (Kb)" ./ffprobe /tmp/poc 2>&1 | tail -n 1 2158192 Max Resident Set Size (Kb) After this change: $ /usr/bin/time