[FFmpeg-devel] [PATCH] Move av_open_input_file probe loop to its own method

[Micah Galizia]

On Wed, Mar 10, 2010 at 5:59 AM, Michael Niedermayer <michaelni at gmx.at>wrote:

> On Mon, Mar 08, 2010 at 08:29:40PM -0500, Micah F. Galizia wrote:
> > On 10-03-07 07:42 PM, M?ns Rullg?rd wrote:
> >> Stefano Sabatini<stefano.sabatini-lala at poste.it>  writes:
> >>
> >>> On date Sunday 2010-03-07 12:48:45 -0500, MIcah Galizia encoded:
> >>>> On 10-03-07 05:52 AM, Stefano Sabatini wrote:
> >>>>> On date Saturday 2010-03-06 19:02:07 -0500, Micah F. Galizia encoded:
> >>>>>> On 10-03-06 06:17 PM, Michael Niedermayer wrote:
> >>> [...]
> >>>>>>> should be ok if tested
> >>>>>>
> >>>>>> I tested it in plain old ffmpeg, and with my shoutcast changes.
> >>>>>
> >>>>> Please test with make test, I tried it and it failed in
> >>>>> regtest-pbmpipe.
> >>>>>
> >>>>> cat pbmpipe.lavf.err
> >>>>> /home/stefano/src/ffmpeg.git/./tests/data/lavf/pbmpipe.pbm: Error
> while
> >>>>> opening file
> >>>>
> >>>> Thank you.  The attached patch fixes it.  The problem was that after
> >>>> the initial probe in av_open_input_file (with no actual probe data),
> >>>> I was setting the input format to NULL in ff_probe_input_buffer.
> >>>> Now all regression tests pass (make test).
> >>>>
> >>>> Also, I have improved the commenting in internal.h.
> >>>>
> >>>> Thanks again!
> >>>
> >>> Patch applied, thanks for the fish.
> >>
> >> This broke ea-cdata on FATE.
> >
> > Actually, it would have broken on any probe score lower than 25 for a
> file
> > smaller than 1MB.  The problem was that the old probe loop would reset
> the
> > file position each time before calling get_buffer. As a result,
> get_buffer
> > would never return AVERROR_EOF, so this wasn't ever a situation that
> needed
> > to be handled.
> >
> > The modified probe just reads on from where it left off in the previous
> > probe, so eventually, the end of file is reached before reaching
> > PROBE_BUF_MAX, so it would just return an error.  It has been updated now
> > to lower the required probe score when the end of file is reached in
> > addition to when PROBE_BUF_MAX is reached.
> >
> > Thanks again, and sorry for breaking FATE!
> > --
> > Micah F. Galizia
> > micahgalizia at gmail.com
> >
> > "The mark of an immature man is that he wants to die nobly for a cause,
> > while the mark of the mature man is that he wants to live humbly for
> one."
> >  --W. Stekel
>
> >  internal.h |   18 +++++++++++
> >  utils.c    |   97
> +++++++++++++++++++++++++++++++++++++++++--------------------
> >  2 files changed, 84 insertions(+), 31 deletions(-)
> > 73e23f49aa0fbc3c6a08b506c3888a40cdddab2f  probe_buffer5.diff
>
> looks good, if tested
>

Make test works, and so does the previously failing test case.
-- 
"The mark of an immature man is that he wants to die nobly for a cause,
while the mark of the mature man is that he wants to live humbly for one."
--W. Stekel