[vlc-devel] [PATCH] core: add "decoder-hw" bool option

[Thomas Guillem]

On Mon, Jan 20, 2020, at 14:45, Rémi Denis-Courmont wrote:
> Hi,
> 
> Conceptually okay but on the implementation level, why do you need to cache the value?

Because I know that some decoders call decoder_UpdateVideoFormat() a lot, for each frames, that is the case for avcodec.
I had an other look, it seems that the decoder device is only requested when needed, so we could get ride of this cache value.

> 
> Le 20 janvier 2020 12:34:59 GMT+02:00, Thomas Guillem <thomas at gllm.fr> a écrit :
>> Enabled by default, this option be used to disable hardware decoders (with
>> "--no-decoder-hw"). This option can be set on input/media items and will be
>> forwarded to the decoder via the input_thread_t.
>> 
>> To disable hardware decoders, the core decoder have to disable decoder devices. src/input/decoder.c | 8 +++++++-
>>  src/libvlc-module.c | 6 ++++++
>>  2 files changed, 13 insertions(+), 1 deletion(-)
>> 
>> diff --git a/src/input/decoder.c b/src/input/decoder.c
>> index 17a36df3c9b..03d92c429c2 100644
>> --- a/src/input/decoder.c
>> +++ b/src/input/decoder.c
>> @@ -129,6 +129,7 @@ struct decoder_owner
>>      vout_thread_t   *p_vout;
>>      enum vlc_vout_order vout_order;
>>      bool            vout_thread_started;
>> +    bool            use_hw;
>>  
>>      /* -- Theses variables need locking on read *and* write -- */
>>      /* Preroll */
>> @@ -615,8 +616,12 @@ static vlc_decoder_device * ModuleThread_GetDecoderDevice( decoder_t *p_dec )
>>      struct decoder_owner *p_owner = dec_get_owner( p_dec );
>>  
>>      enum vlc_vout_order vout_order;
>> +
>> +    /* Requesting a decoder device will automatically enable hw decoding */
>>      vlc_decoder_device *dec_device = NULL;
>> -    int created_vout = CreateVoutIfNeeded(p_owner, NULL, &vout_order, &dec_device);
>> +    vlc_decoder_device **dec_device_ptr = p_owner->use_hw ? &dec_device : NULL;
>> +
>> +    int created_vout = CreateVoutIfNeeded(p_owner, NULL, &vout_order, dec_device_ptr);
>>      if (created_vout == -1)
>>      {
>>          if ( dec_device )
>> @@ -1848,6 +1853,7 @@ static struct decoder_owner * CreateDecoder( vlc_object_t *p_parent,
>>      p_owner->p_aout = NULL;
>>      p_owner->p_vout = NULL;
>>      p_owner->vout_thread_started = false;
>> +    p_owner->use_hw = var_InheritBool( p_parent, "decoder-hw" );
>>      p_owner->i_spu_channel = VOUT_SPU_CHANNEL_INVALID;
>>      p_owner->i_spu_order = 0;
>>      p_owner->p_sout = p_sout;
>> diff --git a/src/libvlc-module.c b/src/libvlc-module.c
>> index 1e733662cf6..9839a8274a9 100644
>> --- a/src/libvlc-module.c
>> +++ b/src/libvlc-module.c
>> @@ -968,6 +968,11 @@ static const char *const ppsz_prefres[] = {
>>      "before trying the other ones. Only advanced users should " \
>>      "alter this option as it can break playback of all your streams." )
>>  
>> +#define DECODER_HW_TEXT N_("Enable hardware decoders")
>> +#define DECODER_HW_LONGTEXT N_( \
>> +    "This will enable hardware decoders. VLC will fallback automatically to " \
>> +    "software decoders in case of hardware decoder failure." )
>> +
>>  #define ENCODER_TEXT N_("Preferred encoders list")
>>  #define ENCODER_LONGTEXT N_( \
>>      "This allows you to select a list of encoders that VLC will use in " \
>> @@ -2044,6 +2049,7 @@ vlc_module_begin ()
>>      add_category_hint(N_("Decoders"), CODEC_CAT_LONGTEXT)
>>      add_string( "codec", NULL, CODEC_TEXT,
>>                  CODEC_LONGTEXT, true )
>> +    add_bool( "decoder-hw", true, DECODER_HW_TEXT, DECODER_HW_LONGTEXT, true )
>>      add_string( "encoder",  NULL, ENCODER_TEXT,
>>                  ENCODER_LONGTEXT, true )
>>      add_module("dec-dev", "decoder device", "any", DEC_DEV_TEXT, DEC_DEV_LONGTEXT)
> 
> -- 
> Envoyé de mon appareil Android avec Courriel K-9 Mail. Veuillez excuser ma brièveté. 
> _______________________________________________
> vlc-devel mailing list
> To unsubscribe or modify your subscription options:
> https://mailman.videolan.org/listinfo/vlc-devel
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.videolan.org/pipermail/vlc-devel/attachments/20200120/7805445f/attachment.html>