[FFmpeg-devel] [PATCH V4] dnn_backend_openvino.c: parse options in openvino backend

[Guo, Yejun]

> -----Original Message-----
> From: ffmpeg-devel <ffmpeg-devel-bounces at ffmpeg.org> On Behalf Of
> Alexander Strasser
> Sent: 2020年8月20日 4:06
> To: FFmpeg development discussions and patches <ffmpeg-devel at ffmpeg.org>
> Subject: Re: [FFmpeg-devel] [PATCH V4] dnn_backend_openvino.c: parse options
> in openvino backend
> 
> Hi Yejun!
> 
> On 2020-08-18 23:08 +0800, Guo, Yejun wrote:
> > Signed-off-by: Guo, Yejun <yejun.guo at intel.com>
> > ---
> > v3: use AVOption
> > v4: don't add new file dnn_common.h/c
> >
> >  libavfilter/dnn/dnn_backend_openvino.c | 50
> > +++++++++++++++++++++++++++++++++-
> >  1 file changed, 49 insertions(+), 1 deletion(-)
> >
> > diff --git a/libavfilter/dnn/dnn_backend_openvino.c
> > b/libavfilter/dnn/dnn_backend_openvino.c
> > index d343bf2..277c313 100644
> > --- a/libavfilter/dnn/dnn_backend_openvino.c
> > +++ b/libavfilter/dnn/dnn_backend_openvino.c
> > @@ -26,9 +26,37 @@
> >  #include "dnn_backend_openvino.h"
> >  #include "libavformat/avio.h"
> >  #include "libavutil/avassert.h"
> > +#include "libavutil/opt.h"
> >  #include <c_api/ie_c_api.h>
> >
> > +typedef struct OVOptions{
> > +    uint32_t batch_size;
> > +    uint32_t req_num;
> > +} OVOptions;
> > +
> > +typedef struct OvContext {
> > +    const AVClass *class;
> > +    OVOptions options;
> > +} OvContext;
> > +
> > +#define OFFSET(x) offsetof(OvContext, x) #define FLAGS
> > +AV_OPT_FLAG_FILTERING_PARAM static const AVOption dnn_ov_options[] =
> > +{
> > +    { "batch",   "batch size",        OFFSET(options.batch_size),
> AV_OPT_TYPE_INT,  { .i64 = 1 }, INT_MIN, INT_MAX, FLAGS },
> > +    { "nireq",   "number of request", OFFSET(options.req_num),
> AV_OPT_TYPE_INT,  { .i64 = 1 }, INT_MIN, INT_MAX, FLAGS },
> > +    { NULL },
> > +};
> 
> If I'm not mistaken, you must use type int when using AV_OPT_TYPE_INT .
> 
> AFAIK we have these integer types
> 
> * AV_OPT_TYPE_INT -> int
> * AV_OPT_TYPE_INT64 -> int64_t
> * AV_OPT_TYPE_UINT64 -> uint64_t
> 
> and you can assume int to be at least 32 bits wide.
> 

thanks, I'll change from uint32_t to int.

> > @@ -186,7 +235,6 @@ DNNModel *ff_dnn_load_model_ov(const char
> *model_filename, const char *options)
> >      model->model = (void *)ov_model;
> >      model->set_input_output = &set_input_output_ov;
> >      model->get_input = &get_input_ov;
> > -    model->options = options;
> >
> >      return model;
> >
> > --
> 
> Sorry, if I missed it, are the values set from the options used anywhere?

You are right, the options are not used. 

My teammates and I are working on the dnn backend performance
improvement, we have done locally many quick dirty code to verify our ideas and
found it requires some changes in the DNN module including these options. 
(In our quick code, we are using fixed magic number for these options)

So, as a collaboration, my idea is to separate the changes one patch by one patch, 
and we can keep rebase locally, the final purpose is to upstream all our local code with refinement.