[FFmpeg-devel] [PATCH] fftools/ffmpeg: use an int for nb_threads

[James Almer]

On 2/14/2025 10:28 PM, Andreas Rheinhardt wrote:
> James Almer:
>> Removes unnecessary allocations.
>>
>> Signed-off-by: James Almer <jamrial at gmail.com>
>> ---
>>   fftools/ffmpeg.h          |  2 +-
>>   fftools/ffmpeg_filter.c   | 16 ++++++----------
>>   fftools/ffmpeg_mux_init.c |  5 ++---
>>   3 files changed, 9 insertions(+), 14 deletions(-)
>>
>> diff --git a/fftools/ffmpeg.h b/fftools/ffmpeg.h
>> index 9439be0f41..6cc0da05a0 100644
>> --- a/fftools/ffmpeg.h
>> +++ b/fftools/ffmpeg.h
>> @@ -316,7 +316,7 @@ typedef struct OutputFilterOptions {
>>       AVDictionary       *sws_opts;
>>       AVDictionary       *swr_opts;
>>   
>> -    const char         *nb_threads;
>> +    int64_t             nb_threads;
>>   
>>       // A combination of OFilterFlags.
>>       unsigned            flags;
>> diff --git a/fftools/ffmpeg_filter.c b/fftools/ffmpeg_filter.c
>> index a0d04fd76f..800e2a3f06 100644
>> --- a/fftools/ffmpeg_filter.c
>> +++ b/fftools/ffmpeg_filter.c
>> @@ -60,7 +60,7 @@ typedef struct FilterGraphPriv {
>>   
>>       const char      *graph_desc;
>>   
>> -    char            *nb_threads;
>> +    int              nb_threads;
>>   
>>       // frame for temporarily holding output from the filtergraph
>>       AVFrame         *frame;
>> @@ -1042,7 +1042,6 @@ void fg_free(FilterGraph **pfg)
>>       }
>>       av_freep(&fg->outputs);
>>       av_freep(&fgp->graph_desc);
>> -    av_freep(&fgp->nb_threads);
>>   
>>       av_frame_free(&fgp->frame);
>>       av_frame_free(&fgp->frame_enc);
>> @@ -1097,6 +1096,7 @@ int fg_create(FilterGraph **pfg, char *graph_desc, Scheduler *sch)
>>       fg->class       = &fg_class;
>>       fgp->graph_desc = graph_desc;
>>       fgp->disable_conversions = !auto_conversion_filters;
>> +    fgp->nb_threads          = -1;
>>       fgp->sch                 = sch;
>>   
>>       snprintf(fgp->log_name, sizeof(fgp->log_name), "fc#%d", fg->index);
>> @@ -1247,12 +1247,8 @@ int fg_create_simple(FilterGraph **pfg,
>>       if (ret < 0)
>>           return ret;
>>   
>> -    if (opts->nb_threads) {
>> -        av_freep(&fgp->nb_threads);
>> -        fgp->nb_threads = av_strdup(opts->nb_threads);
>> -        if (!fgp->nb_threads)
>> -            return AVERROR(ENOMEM);
>> -    }
>> +    if (opts->nb_threads >= 0)
>> +        fgp->nb_threads = opts->nb_threads;
>>   
>>       return 0;
>>   }
>> @@ -1936,8 +1932,8 @@ static int configure_filtergraph(FilterGraph *fg, FilterGraphThread *fgt)
>>               ret = av_opt_set(fgt->graph, "threads", filter_nbthreads, 0);
>>               if (ret < 0)
>>                   goto fail;
>> -        } else if (fgp->nb_threads) {
>> -            ret = av_opt_set(fgt->graph, "threads", fgp->nb_threads, 0);
>> +        } else if (fgp->nb_threads >= 0) {
>> +            ret = av_opt_set_int(fgt->graph, "threads", fgp->nb_threads, 0);
>>               if (ret < 0)
>>                   return ret;
>>           }
>> diff --git a/fftools/ffmpeg_mux_init.c b/fftools/ffmpeg_mux_init.c
>> index 944176ca5d..d212a1f326 100644
>> --- a/fftools/ffmpeg_mux_init.c
>> +++ b/fftools/ffmpeg_mux_init.c
>> @@ -930,7 +930,7 @@ ost_bind_filter(const Muxer *mux, MuxStream *ms, OutputFilter *ofilter,
>>           .ts_offset        = mux->of.start_time == AV_NOPTS_VALUE ?
>>                               0 : mux->of.start_time,
>>           .vs               = vs,
>> -
>> +        .nb_threads       = -1,
>>           .flags = OFILTER_FLAG_DISABLE_CONVERT * !!keep_pix_fmt |
>>                    OFILTER_FLAG_AUTOSCALE       * !!autoscale    |
>>                    OFILTER_FLAG_AUDIO_24BIT * !!(av_get_exact_bits_per_sample(enc_ctx->codec_id) == 24),
>> @@ -982,7 +982,7 @@ ost_bind_filter(const Muxer *mux, MuxStream *ms, OutputFilter *ofilter,
>>       }
>>   
>>       if (threads_manual) {
>> -        ret = av_opt_get(enc_ctx, "threads", 0, (uint8_t**)&opts.nb_threads);
>> +        ret = av_opt_get_int(enc_ctx, "threads", 0, &opts.nb_threads);
>>           if (ret < 0)
>>               return ret;
>>       }
>> @@ -1002,7 +1002,6 @@ ost_bind_filter(const Muxer *mux, MuxStream *ms, OutputFilter *ofilter,
>>               ost->filter = ost->fg_simple->outputs[0];
>>   
>>       }
>> -    av_freep(&opts.nb_threads);
>>       if (ret < 0)
>>           return ret;
>>   
> 
> What about "auto"? I thought that was a thing. Or do I misremember?

Ah, you're right that's an alias for 0.
I guess i could use av_opt_eval_int(), but maybe it's not worth the hassle.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: OpenPGP_signature.asc
Type: application/pgp-signature
Size: 495 bytes
Desc: OpenPGP digital signature
URL: <https://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20250215/1647fab7/attachment.sig>