Decode without repeat first field

[BMart1]

How can I get the progressive samples from the decoder before it applies repeat first field and similar flags? I don't want to deinterlace originally interlaced frames.

[Mark_L_Intel1]

Hi Bruno,

Try to understand your request, do you want to use decode only, input an interlaced stream and output a output stream with the same frame rate but each frame has a double line number? (duplicate each line as the next line to it in output)

You might use the argument "-di <bob or adi>" for sample_decode to do this. Refer to the following document about how to use sample_decode:

 https://github.com/Intel-Media-SDK/samples/blob/master/samples/sample_decode/readme-decode_linux.pdf

Mark 

[BMart1]

Some DVD are encoded as 23.976 progressive and special flags inserted so decoders do telecine to generate 29.97 interlaced frames. Does the mfx encoder support this? Can the mfx decoder ignore the flags and return the original 23.976 progressive frames?

[BMart1]

I think you can feed the encoder fields marked with MFX_PICSTRUCT_FIELD_REPEATED and get soft telecine, but I still cannot find how to get it from the decoder.

[Mark_L_Intel1]

Hi Martinez,

So you want this special video of progressive with interlaced flag set in the stream? In this case, your app should prefer not to do deinterlacing.

Normally the configuration sequence in the decode app is:

1. Set the initial parameters

2. Read the stream header and overwrite the parameters in #1 with the new parameters from stream.

3. Decoding

I think you might to check you code to make sure, the progressive parameter is set between #2 and #3.

Mark

[BMart1]

So which initial parameters do I use to prevent the decoder from assembling interlaced frames from source progressive frames?

[Mark_L_Intel1]

You can download our tutorial 0.0.4 at the following page:

https://software.intel.com/en-us/media-sdk/training

You can get the initial parameters example from simple_decode project. In general, any parameter is fine because they will be overwrite by the input from the stream header.

Mark 

[BMart1]

Sorry Mark, I don't understand. What configuration disables interlacing in the decoder?

[BMart1]

Let me answer my own question: With mfxInfoMFX::ExtendedPicStruct decoding gives you raw encoded frames without repeats.

[Mark_L_Intel1]

Hi Bruno,

Sorry I missed your question, did you find the solution yet?

Mark

[BMart1]

Yes, thanks Mark.