[FFmpeg-devel] [PATCH] avformat: export probe score

[Reimar Döffinger]

Paul B Mahol <onemda at gmail.com> wrote:
>On 8/9/13, Michael Niedermayer <michaelni at gmx.at> wrote:
>> On Thu, Aug 08, 2013 at 09:44:44PM +0000, Paul B Mahol wrote:
>>> On 8/8/13, Michael Niedermayer <michaelni at gmx.at> wrote:
>>> > Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
>>> > ---
>>> >  libavformat/avformat.h      |   17 +++++++++++++++--
>>> >  libavformat/options_table.h |    1 +
>>> >  libavformat/utils.c         |   18 ++++++++++++++----
>>> >  3 files changed, 30 insertions(+), 6 deletions(-)
>>> >
>>> > diff --git a/libavformat/avformat.h b/libavformat/avformat.h
>>> > index d5f8a29..6afdcf5 100644
>>> > --- a/libavformat/avformat.h
>>> > +++ b/libavformat/avformat.h
>>> > @@ -1237,6 +1237,13 @@ typedef struct AVFormatContext {
>>> >       */
>>> >      int flush_packets;
>>> >
>>> > +    /**
>>> > +     * format probing score
>>> > +     * - encoding: unused
>>> > +     * - decoding: set by avformat, read by user via AVOPtions
>(NO
>>> > direct
>>> > access)
>>> > +     */
>>> > +    int probe_score;
>>> > +
>>>
>>> Should't this above be bellow?
>>
>> it is intended to be public API, so i would say no
>
>But than it would break with fork, wouldn't it?
>
>>
>> [...]
>>> > diff --git a/libavformat/options_table.h
>b/libavformat/options_table.h
>>> > index a87868e..cf7f2da 100644
>>> > --- a/libavformat/options_table.h
>>> > +++ b/libavformat/options_table.h
>>> > @@ -76,6 +76,7 @@ static const AVOption avformat_options[] = {
>>> >  {"skip_initial_bytes", "skip initial bytes",
>>> > OFFSET(skip_initial_bytes),
>>> > AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX-1, D},
>>> >  {"correct_ts_overflow", "correct single timestamp overflows",
>>> > OFFSET(correct_ts_overflow), AV_OPT_TYPE_INT, {.i64 = 1}, 0, 1,
>D},
>>> >  {"flush_packets", "enable flushing of the I/O context after each
>>> > packet",
>>> > OFFSET(flush_packets), AV_OPT_TYPE_INT, {.i64 = 1}, 0, 1, E},
>>> > +{"probe_score", "score with which the format was probed",
>>> > OFFSET(probe_score), AV_OPT_TYPE_INT, {.i64 = 0}, 0,
>AVPROBE_SCORE_MAX,
>>> > D},
>>>
>>> Hmm? What is this suppose to do?
>>
>> allow the user to find out the score by which some container was
>> detected/probed
>
>But those are used primarly to set values by caller.
>Yes I know that we do not care for consistency at all.
>
>At least there should be separation between read-only options - for
>caller pov and others.
>As changing this value doesn't makes sense for user.

Should it be read-only though?
For the probe function you'd actually pass in a minimum score needed to detect a format. Might actually be useful for command-line uses of FFmpeg itself where people can't add their own code after all...