[FFmpeg-devel] [Internet][PATCH 00/12] Add MediaCodec encoder and NDK MediaCodec support

"zhilizhao(赵志立)" quinkblack at foxmail.com
Thu Nov 17 04:36:27 EET 2022


On Nov 11, 2022, at 11:36, zhilizhao(赵志立) <quinkblack at foxmail.com> wrote:
> 
> Ping for review.

I’m planning to push this week if no more comments.

> 
>> On Oct 24, 2022, at 11:16, Zhao Zhili <quinkblack at foxmail.com> wrote:
>> 
>> From: Zhao Zhili <zhilizhao at tencent.com>
>> 
>> Firstly, some bugs were fixed (patch 1-4).
>> 
>> Patch 5 and 6 make mediacodec_wrapper support Java MediaCodec and NDK
>> MediaCodec. The use case I'm considering is run FFmpeg on cmdline without JVM,
>> for example, run FFmpeg inside of termux (an Android terminal emulator). It's
>> well known that NDK MediaCodec missing some important functions, like get the
>> list of codecs, but still useable.
>> 
>> Patch 7 add NDK MediaCodec decoder support. It can be enabled via options,
>> and enabled automatically if no JVM is available.
>> 
>> Patch 8 add ANativeWindow support to hwcontext_mediacodec. It can be set by
>> user, and can be created via AMediaCodec_createPersistentInputSurface
>> automatically. This is a preparation for encoder.
>> 
>> Patch 9 makes MediaCodec decoder to support ANativeWindow directly. It worth
>> to note that AVMediaCodecContext has only surface. Although we provided
>> av_mediacodec_alloc_context(), we didn't strictly prevent users to allocate
>> AVMediaCodecContext on stack. I'm not sure if it's OK to add new field to
>> AVMediaCodecContext.
>> 
>> Patch 10 add MediaCodec encoder support. Frame can be feed to encoder via
>> buffer, or via Surface/ANativeWindow. If Surface/ANativeWindow is used, and
>> the frames come from our MediaCodec decoder wrapper, we can control it's
>> 'render' (send to encoder's surface) via av_mediacodec_release_buffer(). A DTS
>> generation strategy works in this case. However, if frames comes from other
>> sources, like a camera, there is no way to control the 'render' yet, so DTS is
>> missing in this case.
>> 
>> Finally, we can do mediacodec transcoding with FFmpeg cmdline on Android.
>> More importantly, we can do MediaCodec decoder to encoder without copy frames,
>> although it's very limited since most of avfilters doesn't work. For example:
>> 
>> ./ffmpeg -hwaccel mediacodec -hwaccel_output_format mediacodec -i /sdcard/test.mp4 -an -c:v h264_mediacodec -y /sdcard/out.mp4
>> 
>> Since there is no real AVHWFrameContext implementation in hwcontext_mediacodec.
>> there is no hwframe_ctx for mediacodec and av_hwframe_transfer_data() doesn't
>> work. So if -hwaccel_output_format isn't being specified like:
>> 
>> ./ffmpeg -hwaccel mediacodec -i /sdcard/test.mp4 -an -c:v h264_mediacodec -y /sdcard/out.mp4
>> 
>> It will trigger a crash in av_hwframe_transfer_data. Patch 11 add a check on
>> hwframe_ctx. Patch 12 set hwaccel_output_format automatically to avoid such
>> case.
>> 
>> 
>> Zhao Zhili (12):
>> avcodec/mediacodec: fix incorrect crop info
>> avcodec/mediacodecdec: don't break out if both input and output port
>>   return try again
>> avcodec/mediacodecdec_common: fix misuse av_free/av_freep
>> avcodec/mediacodecdec_common: fix useless av_buffer_unref
>> avcodec/mediacodec_wrapper: separate implementation from interface
>> avcodec/mediacodec: add NDK media codec wrapper
>> avcodec/mediacodecdec: enable NDK mediacodec
>> avutil/hwcontext_mediacodec: add ANativeWindow support
>> avcodec/mediacodec: add ANativeWindow support
>> avcodec: add MediaCodec encoder
>> avutil/hwcontext: verify hw_frames_ctx in transfer_data_alloc
>> fftools/ffmpeg_opt: set default hwaccel_output_format for mediacodec
>> 
>> Changelog                         |   2 +
>> configure                         |   6 +
>> fftools/ffmpeg_opt.c              |   4 +
>> libavcodec/Makefile               |   2 +
>> libavcodec/allcodecs.c            |   2 +
>> libavcodec/mediacodec_surface.c   |  46 +-
>> libavcodec/mediacodec_surface.h   |   8 +-
>> libavcodec/mediacodec_wrapper.c   | 942 +++++++++++++++++++++++++++---
>> libavcodec/mediacodec_wrapper.h   | 275 +++++++--
>> libavcodec/mediacodecdec.c        |  21 +-
>> libavcodec/mediacodecdec_common.c |  35 +-
>> libavcodec/mediacodecdec_common.h |   1 +
>> libavcodec/mediacodecenc.c        | 495 ++++++++++++++++
>> libavcodec/version.h              |   2 +-
>> libavutil/hwcontext.c             |   6 +-
>> libavutil/hwcontext_mediacodec.c  |  56 +-
>> libavutil/hwcontext_mediacodec.h  |  11 +
>> libavutil/version.h               |   4 +-
>> 18 files changed, 1780 insertions(+), 138 deletions(-)
>> create mode 100644 libavcodec/mediacodecenc.c
>> 
>> -- 
>> 2.25.1
>> 
>> 
> 
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