On Fri, Feb 15, 2013 at 1:27 AM, Lars Hammarstrand
wrote:
>
>> However, not only that, it would also require exporting a ff* private
>> symbol from avutil, and adds a lot of complexity when dealing with
>> shared library builds on some systems (eg. MSVC)
>
>
> This is one part that I don't underst
I need to do this because in the documentation of FFMPEG, for the
avcodec_decode_video2, there's a Warning:
The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than the actual
read bytes because some optimized bitstream readers read 32 or 64 bits at once
and could read over the end.
'Morning!
I guess there are a number of people on here who are experts at writing
optimised code exploiting every bit of a processor's instruction set. The code
I recently isolated from the Perian project also attempts this, and I just came
across something that got flabbergasted me. Perian is
>Everything prefixed with ff are private symbols in ffmpeg, and as such
>are not supposed to be exposed in link libraries, because they are not
>part of the public API/ABI.
>There are already too many exceptions to this, and this avoided even
>more.
This pleads for static local copies.
BTW, would
Chris Share wrote:
>Thanks for the sample code.
>
>I have a couple of further questions:
>
>1. If the input data is in a vector of unsigned chars (RGBRGB...), what
>is the best pixel format to use?
I think that'd by FMT_RGB24 .
R
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2013/2/15 René J.V. Bertin
>
> This pleads for static local copies.
>
>
Yeah, this is what I would suggest too.
If the objective is to have portable static libraries, don't define global
symbol multiple times, it's just the wrong way of working. This is
especially true for static libraries in ru
2013/2/14 "René J.V. Bertin"
> Since you clearly have the your-ended problem of working in a context
> where multiple ff_log2_tabs bite, I suggest the open libavutil/intmath.h ,
> and on line 53 or so you replace
>
> extern const uint8_t ff_log2_tab[256];
>
> by
>
> static const uint8_t ff_log2_t
On Fri, Feb 15, 2013 at 6:37 AM, "René J.V. Bertin" wrote:
> On my 2.7Ghz dual-core i7 MBP, I get about 1Hz for the SSE version, and
> roughly half that for the generic, scalar function, using gcc-4.2 as well as
> using MSVC 2010 Express running under WinXP in VirtualBox. The factor 2 speed
Thanks, Claudio!
On Feb 15, 2013, at 16:33, Claudio Freire wrote:
> gcc 4.7 is clever enough to generate SSE code by itself. Maybe that's
> what you're experiencing. I guess compiler flags do matter too.
I haven't compiled with -ftree-vectorize (rather, I tried with and without,
made no differe
On Fri, Feb 15, 2013 at 12:48 PM, "René J.V. Bertin"
wrote:
> On Feb 15, 2013, at 16:33, Claudio Freire wrote:
>
>> gcc, which tends to inhibit many of its other optimizations. Why don't
>> you try gcc's vector primitives instead?
>
> Which ones?
Well, you specify "memory" so it will inhibit all
On Feb 15, 2013, at 17:08, Claudio Freire wrote:
>
> SSE intrinsics (and automatic vectorization in fact) perform a lot
> more poorly if you don't use __builtin_assume_aligned[0]
>
>
> [0] http://gcc.gnu.org/projects/tree-ssa/vectorization.html#assume-aligned
Ah, of course ... but OS X memory
2013/2/15 Lars Hammarstrand
> 2013/2/14 "René J.V. Bertin"
>
>> Since you clearly have the your-ended problem of working in a context
>> where multiple ff_log2_tabs bite, I suggest the open libavutil/intmath.h ,
>> and on line 53 or so you replace
>>
>>
I'm kind of lazy so I used a slightly diff
On 11/02/13 12:18, pepe...@yahoo.com wrote:
Hi,
Is there a 'correct' way to pass DVD NAV packets back to a demuxer? At the
moment, we're calling 'av_read_frame', which eventually lands in a function
which interfaces with libdvdnav to retrieve the DVD packets. The DVD NAV
packets contain pri
Hi all,
I am currently using avcodec to decode my stream. As you all
know, you need to point to the right inttypes.h in order avcodec to be
working well. Therefore, I have put the inttypes.h under /include folder
and include this folder in my project. This works great on Windows.
However, I n
There's not a better type, it depends on the whole system.
For instance, that's a part of a video capture utility. I recieve the
"ptBuffer", or the source image, in YUV422 (which is a very common pixel
format in capture cards and video cameras). I do the rescale as well as the
pixel format convers
Hello Friends,
Good Morning.
Trust doing fine.
I am developing a application that convert one video to another including
sound (means in source file has video as well as sound) with the help of
FFMPEG Library I have created a video. But sound is not available in
converted video. so please help me
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