what are transform filters and source filters?

[Mohammad48]

what are transform filters and source filters? i see them in k-lite codec pack mega under options > internal filters


are they video/audio decoder ?

[hello_hello]

https://en.wikipedia.org/wiki/DirectShow#Architecture
Source filters
These provide the source streams of data. For example, reading raw bytes from any media file.
Transform filters
These transform data that is provided from other filter's output. For example, doing a transform such as adding text on top of video or uncompressing an MPEG frame.

It sounds like the k-lite options for internal filters are configuring whether MPC-HC uses it's internal filters or system (DirectShow) installed filters but I don't know for sure as I don't use k-lite. If that's what it is, the MPC-HC option for internal filters normally looks like this:



You'd select a source filter for a file type on the left. If you de-select one, MPC-HC would use a system source filter for that file type instead, if there's an appropriate on available. Otherwise, if they're selected I think the LAV splitter is used.

If a transform filter on the right is selected, the internal audio or video decoder will be used for that type (LAV audio or video decoder). If it's de-selected, MPC-HC will use an appropriate DirectShow decoder instead (ie something like ffdshow) assuming an appropriate directshow decoder is installed.

In my case I have most audio types de-selected as I prefer to use the ffdshow audio decoder for decoding audio as I use some of it's filters (equaliser etc).

Just in case it causes confusion, the LAV filters can be downloaded and installed separately, just as you can download and install the ffdshow codec, but these days MPC-HC also uses LAV for it's internal filters. Whether or not k-lite changes that, I have no idea. I kind of remember k-lite used to install a stripped down version of MPC-HC with no internal filters, but I don't know if it still does.

[Mohammad48]

does the source filter identify the container and sound/video/subtitle tracks?

[El Heggunte]

does the source filter identify the container and sound/video/subtitle tracks?

The media player detects the container type AND chooses the appropriate demultiplexer. Then this latter identifies the stream types, and "calls" the associated decoders. Finally, the decompressed audio and video (plus subtitles, if any) are sent to the respective renderers.

[Mohammad48]

thanks hello_hello and El Heggunte.