[FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

A lot of codecs require aligned frame data, but do not document it. It can result in crashes with perfectly valid uses of the API. Design rationale: - requiring frame data to be always aligned would be wasteful; - alignment requirements will evolve (the 16->32 bump is still recent); -

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

On Wed, May 10, 2017 at 06:46:41PM -0400, Ronald S. Bultje wrote: > Hi, > > On Wed, May 10, 2017 at 5:02 PM, Michael Niedermayer > wrote: > > > On Wed, May 10, 2017 at 10:28:22PM +0200, Nicolas George wrote: > > > Le primidi 21 floréal, an CCXXV, Michael Niedermayer a

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

Hi, On Wed, May 10, 2017 at 5:02 PM, Michael Niedermayer wrote: > On Wed, May 10, 2017 at 10:28:22PM +0200, Nicolas George wrote: > > Le primidi 21 floréal, an CCXXV, Michael Niedermayer a écrit : > > > fixed, and now your patchset seems to cause a 1% slowdown of the >

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

On Wed, May 10, 2017 at 10:28 PM, Nicolas George wrote: > Le primidi 21 floréal, an CCXXV, Michael Niedermayer a écrit : >> fixed, and now your patchset seems to cause a 1% slowdown of the >> example above > > Thanks. The slowdown is to be expected, since this filter used >

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

On Wed, May 10, 2017 at 10:28:22PM +0200, Nicolas George wrote: > Le primidi 21 floréal, an CCXXV, Michael Niedermayer a écrit : > > fixed, and now your patchset seems to cause a 1% slowdown of the > > example above > > Thanks. The slowdown is to be expected, since this filter used > non-aligned

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

On 5/10/17, Michael Niedermayer wrote: > On Wed, May 10, 2017 at 05:49:20PM +0200, Nicolas George wrote: >> Le primidi 21 floreal, an CCXXV, Michael Niedermayer a ecrit : >> > breaks (green stuff on edges) >> > ./ffmpeg -i ~/videos/matrixbench_mpeg2.mpg -an -vframes 5

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

Le primidi 21 floréal, an CCXXV, Michael Niedermayer a écrit : > fixed, and now your patchset seems to cause a 1% slowdown of the > example above Thanks. The slowdown is to be expected, since this filter used non-aligned frames which are now realigned. I guess you can get back the previous speed

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

On Wed, May 10, 2017 at 05:49:20PM +0200, Nicolas George wrote: > Le primidi 21 floréal, an CCXXV, Michael Niedermayer a écrit : > > breaks (green stuff on edges) > > ./ffmpeg -i ~/videos/matrixbench_mpeg2.mpg -an -vframes 5 -vf uspp=4:8 > > -qscale 1 -y file.avi > > It is a bug in vf_uspp: >

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

Le primidi 21 floréal, an CCXXV, Michael Niedermayer a écrit : > breaks (green stuff on edges) > ./ffmpeg -i ~/videos/matrixbench_mpeg2.mpg -an -vframes 5 -vf uspp=4:8 > -qscale 1 -y file.avi It is a bug in vf_uspp: diff --git a/libavfilter/vf_uspp.c b/libavfilter/vf_uspp.c index

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

On Wed, May 10, 2017 at 04:16:25AM +0200, Michael Niedermayer wrote: > On Tue, May 09, 2017 at 03:19:43PM +0200, Nicolas George wrote: > > A lot of codecs require aligned frame data, but do not document it. > > It can result in crashes with perfectly valid uses of the API. > > > > Design

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

On Tue, May 09, 2017 at 03:19:43PM +0200, Nicolas George wrote: > A lot of codecs require aligned frame data, but do not document it. > It can result in crashes with perfectly valid uses of the API. > > Design rationale: > > - requiring frame data to be always aligned would be wasteful; > > -

[FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

A lot of codecs require aligned frame data, but do not document it. It can result in crashes with perfectly valid uses of the API. Design rationale: - requiring frame data to be always aligned would be wasteful; - alignment requirements will evolve (the 16->32 bump is still recent); -

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

Hi, On Sun, May 7, 2017 at 2:55 PM, Hendrik Leppkes wrote: > On Sun, May 7, 2017 at 7:17 PM, Ronald S. Bultje > wrote: > > Hi, > > > > On Sun, May 7, 2017 at 11:15 AM, Hendrik Leppkes > > wrote: > > > >> Ronald suggested on IRC

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

On Sun, May 7, 2017 at 7:17 PM, Ronald S. Bultje wrote: > Hi, > > On Sun, May 7, 2017 at 11:15 AM, Hendrik Leppkes > wrote: > >> Ronald suggested on IRC that the only parts suffering from this are >> the ASM DSP components, and we should just make

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

Hi, On Sun, May 7, 2017 at 11:15 AM, Hendrik Leppkes wrote: > Ronald suggested on IRC that the only parts suffering from this are > the ASM DSP components, and we should just make checkasm tests for all > of them and let checkasm test the alignment they claim to support,

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

On Sat, May 6, 2017 at 8:34 PM, Nicolas George wrote: > > Encouraging the applications to be aware of the issue for performances > reasons is a good thing. > > Forcing them to do so when it is not convenient, on pain of crash, when > it can be done for them just as easily, not so

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

Le septidi 17 floréal, an CCXXV, Hendrik Leppkes a écrit : > I don't think this is very practical. We have a bunch of generic DSPs > and if a codec uses those it would need to be constantly updated if > the requirements of those DSPs change. Today it may only use SSE and > be happy with 16-byte

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

Le septidi 17 floréal, an CCXXV, Ronald S. Bultje a écrit : > I agree it's likely that one codec (e.g. h264) would need 32-byte alignment > on a particular system (e.g. x86/haswell), whereas another codec on the > same system (e.g. wmavoice) might not. > > However, I find it unlikely that one

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

On Sat, 6 May 2017, Ronald S. Bultje wrote: Hi, On Sat, May 6, 2017 at 5:20 AM, Nicolas George wrote: +/** + * Minimum alignment of frame data required by the codec. + * All frame data pointers must have the alignment lower bits cleared, + * i.e. be a

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

Hi, On Sat, May 6, 2017 at 5:20 AM, Nicolas George wrote: > +/** > + * Minimum alignment of frame data required by the codec. > + * All frame data pointers must have the alignment lower bits cleared, > + * i.e. be a multiple of 1< + * - encoding: set by the

Re: [FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

On Sat, May 6, 2017 at 11:20 AM, Nicolas George wrote: > A lot of codecs require aligned frame data, but do not document it. > It can result in crashes with perfectly valid uses of the API. > > TODO Implementation missing. > > Design rationale: > > - requiring frame data to be

[FFmpeg-devel] [PATCH 2/3] lavc: add a framework to fix alignment problems.

A lot of codecs require aligned frame data, but do not document it. It can result in crashes with perfectly valid uses of the API. TODO Implementation missing. Design rationale: - requiring frame data to be always aligned would be wasteful; - alignment requirements will evolve (the 16->32