How to get decode format from MediaCodec?

问题

I am working with MediaCodec

I am using it for decode .mp4 video

MediaCodec decode a video to YUV format, but I need to get RGBA

All is ok, but I found out that there is a few possible formats like YUV420, YUV422 and so on...

So, as far as I understand to make conversion I need to know exactly which conversion to apply YUV420_to_RGBA or YUV422_to_RGBA or something else...

So, question is - how using MediaCodec get know about decoding format?

Feel free to ask.

EDIT

I found out that this way I can get COLOR_FORMAT

 AMediaFormat_getInt32(format, AMEDIAFORMAT_KEY_COLOR_FORMAT, &format_color);

But, I get number 117 ...

How to know what is this number equals?

回答1:

Thanks to @fadden eventually I found the problem, I tried to get AMEDIAFORMAT_KEY_COLOR_FORMAT from not right AMediaFormat...

It was like this NOT RIGHT

AMediaFormat *format = AMediaExtractor_getTrackFormat(ex, i);
int format_color;
AMediaFormat_getInt32(format, AMEDIAFORMAT_KEY_COLOR_FORMAT, &format_color);

Here format_color was 117 - some not valid value...

Right way to get AMEDIAFORMAT_KEY_COLOR_FORMAT is

AMediaCodec *codec = AMediaCodec_createDecoderByType(mime);
AMediaCodec_configure(codec, format, nullptr, nullptr, 0);
AMediaCodec_start(codec);
int format_color;
auto format = AMediaCodec_getOutputFormat(codec);
AMediaFormat_getInt32(format, AMEDIAFORMAT_KEY_COLOR_FORMAT, &format_color);

Here format_color = 21 according to this https://developer.android.com/reference/android/media/MediaCodecInfo.CodecCapabilities.html 21 is COLOR_FormatYUV422Flexible

来源：https://stackoverflow.com/questions/56935547/how-to-get-decode-format-from-mediacodec