[FFmpeg-devel] [PATCH 1/2] lavfi/opencl: Use filter device if no input device is available

[Mark Thompson]

On 03/01/18 06:57, Jun Zhao wrote:
> On 2018/1/3 7:12, Mark Thompson wrote:
>> This allows implementing sources as well as filters.
>> ---
>>  libavfilter/opencl.c | 39 +++++++++++++++++++++++++++++++++------
>>  1 file changed, 33 insertions(+), 6 deletions(-)
>>
>> diff --git a/libavfilter/opencl.c b/libavfilter/opencl.c
>> index 005ad089e2..37afc41f8b 100644
>> --- a/libavfilter/opencl.c
>> +++ b/libavfilter/opencl.c
>> @@ -42,11 +42,29 @@ int ff_opencl_filter_query_formats(AVFilterContext *avctx)
>>      return ff_set_common_formats(avctx, formats);
>>  }
>>  
>> +static int opencl_filter_set_device(AVFilterContext *avctx,
>> +                                    AVBufferRef *device)
>> +{
>> +    OpenCLFilterContext *ctx = avctx->priv;
>> +
>> +    av_buffer_unref(&ctx->device_ref);
>> +
>> +    ctx->device_ref = av_buffer_ref(device);
>> +    if (!ctx->device_ref)
>> +        return AVERROR(ENOMEM);
>> +
>> +    ctx->device = (AVHWDeviceContext*)ctx->device_ref->data;
>> +    ctx->hwctx  = ctx->device->hwctx;
>> +
>> +    return 0;
>> +}
>> +
>>  int ff_opencl_filter_config_input(AVFilterLink *inlink)
>>  {
>>      AVFilterContext   *avctx = inlink->dst;
>>      OpenCLFilterContext *ctx = avctx->priv;
>>      AVHWFramesContext *input_frames;
>> +    int err;
>>  
>>      if (!inlink->hw_frames_ctx) {
>>          av_log(avctx, AV_LOG_ERROR, "OpenCL filtering requires a "
>> @@ -59,15 +77,12 @@ int ff_opencl_filter_config_input(AVFilterLink *inlink)
>>          return 0;
>>  
>>      input_frames = (AVHWFramesContext*)inlink->hw_frames_ctx->data;
>> -
>>      if (input_frames->format != AV_PIX_FMT_OPENCL)
>>          return AVERROR(EINVAL);
>>  
>> -    ctx->device_ref = av_buffer_ref(input_frames->device_ref);
>> -    if (!ctx->device_ref)
>> -        return AVERROR(ENOMEM);
>> -    ctx->device = input_frames->device_ctx;
>> -    ctx->hwctx  = ctx->device->hwctx;
>> +    err = opencl_filter_set_device(avctx, input_frames->device_ref);
>> +    if (err < 0)
>> +        return err;
>>  
>>      // Default output parameters match input parameters.
>>      if (ctx->output_format == AV_PIX_FMT_NONE)
>> @@ -90,6 +105,18 @@ int ff_opencl_filter_config_output(AVFilterLink *outlink)
>>  
>>      av_buffer_unref(&outlink->hw_frames_ctx);
>>  
>> +    if (!ctx->device_ref) {
> I  think AVFilter framework call ff_opencl_filter_config_input first, is
> it need to check !ctx->device_ref？

If you have a filter then config_input is indeed called first and the device from the first input is used, but if you have a source rather than a filter (no inputs) then you need this test to get the device from the filter setup.  See how openclsrc works in patch 1/2.

>> +        if (!avctx->hw_device_ctx) {
>> +            av_log(avctx, AV_LOG_ERROR, "OpenCL filtering requires an "
>> +                   "OpenCL device.\n");
>> +            return AVERROR(EINVAL);
>> +        }
>> +
>> +        err = opencl_filter_set_device(avctx, avctx->hw_device_ctx);
>> +        if (err < 0)
>> +            return err;
>> +    }
>> +
>>      output_frames_ref = av_hwframe_ctx_alloc(ctx->device_ref);
>>      if (!output_frames_ref) {
>>          err = AVERROR(ENOMEM);
> 

Thanks,

- Mark