Replacing the standard Android H264 software encoder with an ffmpeg based one

Question

In Android ICS and later, a new OpenMax IL API version is in use, making old binary blobs useless/unused. This leads to older devices that otherwise run ICS just fine and dandy to have broken video playback (YouTube HQ and IMBD, for example) because Androids fallback software decoder sucks when compared to what ffmpeg can do on the same device (I tested MXPlayer+arm6vfp ffmpeg and a 720p movie played back great).

I am trying to dig through the Android source code to see where and what exactly I could add/replace code to allow the ffmpeg library's awesomeness to be used. The problem is I don't know exactly what code is being used in for example the YouTube app to decode video, or how that's decided.

So I have two options as far as I can tell:

1. Figure out the current software decoder being used, and try to wrap its external interface around ffmpeg, effectively replacing the slow software decoder currently used. The end result would be a single .so I could push to the device.

2. Figure out how to trick Android into thinking an OMX library based on ffmpeg (I have built one succesfully for Android: limoa) and add this somewhere to the list of considered libraries (or better: replace the unusable hardware codec).

As an extension, I'd like to also make camcorder video encoding work through this, so a true integrated solution would be very much wanted. The question is: how, and where, and what? Searching the Android source tree gives numerous counts of "H264" and related stuff in many different places. I need the lowest and simplest possible, so I can simply wrap the hypothetical decode(buffer) function call to use ffmpeg (libavcodec).

Answer 1

It seems to me that this presentation ("Integrating a Hardware Video Codec into Android Stagefright using OpenMAX IL") is exactly what you'd like to do. Good luck with your project!