[FFmpeg-devel] qt-faststart update

[Baptiste Coudurier]

Hi,

On 6/26/2009 11:51 AM, Frank Barchard wrote:
> On Wed, Jun 24, 2009 at 11:58 PM, Reimar D?ffinger <Reimar.Doeffinger at gmx.de
>> wrote:
> 
>> On Wed, Jun 24, 2009 at 07:29:16PM -0300, Ramiro Polla wrote:
>>> On Wed, Jun 24, 2009 at 6:22 PM, Reimar D?ffinger
>>> <Reimar.Doeffinger at gmx.de>wrote:
>>>
>>>> On Wed, Jun 24, 2009 at 10:07:47PM +0200, Karl Blomster wrote:
>>>>> Frank Barchard wrote:
>>>>>> Thank!  The types should be possible to deal with.  Any suggestions
>> for
>>>> a
>>>>>> portable 64 bit fseek?
>>>>> I think
>>>>>
>>>>> #ifdef _WIN32
>>>>> #    ifdef __MINGW32__
>>>>> #        define fseeko fseeko64
>>>>> #      define ftello ftello64
>>>>> #    else
>>>>> #        define fseeko _fseeki64
>>>>> #        define ftello _ftelli64
>>>>> #    endif
>>>>> #endif
>>>>>
>>>>> is the closest you're going to get.
>>>> See MinGW patches to add this feature. There is already a bug report
>> with
>>>> an unfinished patch. That is the only proper place.
>>> I think that patch doesn't fit here... He wants VC support, not MinGW32.
>> Well... I think the basic idea would still be very similar. There is
>> already a inttypes.h reimplementation for VC, something similar could
>> probably be done for stdio.h, too, with some hacks for 64 bit file
>> access support.
> 
> 
> Upgrading to VS2008 didn't help with types or fseeko.  I'll look at VS2010.
>  If the code wont come to the compiler, maybe the compiler will come to the
> code :)
> 
> Removing VC support and using 1k blocks, I was concerned about loosing
> performance.  (Muxing and running qt-faststart is more of a bottleneck than
> I expected)
> First I compare mp4box to ffmpeg for mux performance.  I run it on one
> drive, vs two drives where the destination is a different folder
> ffmpeg -y -r 23.976 -i sonyh2.m4a -i sonyh.264 -vcodec copy -acodec copy
> sonyh2.m4v
> 
> Muxer Time (milliseconds) Time (minutes)
> ffmpeg 1 drive 1,326,533.07 22.11
> ffmpeg 2 drives 1,295,611.71 21.59
> mp4box 1 drive 10,386,286.79 173.10
> mp4box 2 drives 13,068,641.76 217.81
> qt-faststart.vc32k 1 drive 1,384,525.08 23.08
> qt-faststart.vc32k 2 drive 242,990.97 4.05
> qt-faststart.gcc1k 1 drive 1,375,145.10 22.92
> qt-faststart.gcc1k 2 drive 225,813.66 3.76
>
> Total test 29,317,694.07 488.63
> 
> So the GCC version runs great, but is just as slow as ffmpeg mux. It would
> be nice not to need this step.

Does this mean that ffmpeg+qtfaststart on 2 drives is still ~= 8 times
faster that mp4box ? Or did I misunderstood the numbers ?

The time with mp4box on 2 drives is weird though.

[...]

-- 
Baptiste COUDURIER                              GnuPG Key Id: 0x5C1ABAAA
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