Commit Graph

3 Commits

Author SHA1 Message Date
Yunqing Wang
fa1a9290e6 Allow to skip highest-resolution encoding in multi-resolution encoder
Sometimes, a user doesn't have enough bandwidth to send high-resolution
(i.e. HD) video even though the camera catches HD video. This change
allowed users to skip highest-resolution encoding by setting that level's
target bit rate to 0.

To test it, modify the following line in vp8_multi_resolution_encoder.c.
    unsigned int  target_bitrate[NUM_ENCODERS]={1400, 500, 100};
To skip the highest-resolution level, change it to
    unsigned int  target_bitrate[NUM_ENCODERS]={0, 500, 100};
To skip the first and second highest resolution levels, change it to
    unsigned int  target_bitrate[NUM_ENCODERS]={0, 0, 100};

This change also fixed a small problem in mapping, which slightly helped
quality and performance.

Change-Id: I977bae9a9fbfba85c8be4bd5af01539f2b84bc81
2012-02-03 13:39:05 -05:00
Yunqing Wang
153eec46e0 Align image buffer in multiple-resolution encoder
Aligned the image buffer and stride to 32 bytes. This enables
calling of optimized scaler function in libyuv, and improves
the performance.

Tested libyuv scaler(x86 optimization) on Linux and Windows,
including: Linux 32/64bit, visual studio 32/64bit, Cygwin, and
MinGW32.

Also, fixed a wrong pointer in vpx_codec_encode().

Change-Id: Ibe97d7a0a745f82c43852fa4ed719be5a4db6abc
2011-12-13 09:25:30 -05:00
Yunqing Wang
aa7335e610 Multiple-resolution encoder
The example encoder down-samples the input video frames a number of
times with a down-sampling factor, and then encodes and outputs
bitstreams with different resolutions.

Support arbitrary down-sampling factor, and down-sampling factor
can be different for each encoding level.

For example, the encoder can be tested as follows.
1. Configure with multi-resolution encoding enabled:
../libvpx/configure --target=x86-linux-gcc --disable-codecs
--enable-vp8 --enable-runtime_cpu_detect --enable-debug
--disable-install-docs --enable-error-concealment
--enable-multi-res-encoding
2. Run make
3. Encode:
If input video is 1280x720, run:
./vp8_multi_resolution_encoder 1280 720 input.yuv 1.ivf 2.ivf 3.ivf 1
(output: 1.ivf(1280x720); 2.ivf(640x360); 3.ivf(320x180).
The last parameter is set to 1/0 to show/not show PSNR.)
4. Decode:
./simple_decoder 1.ivf 1.yuv
./simple_decoder 2.ivf 2.yuv
./simple_decoder 3.ivf 3.yuv
5. View video:
mplayer 1.yuv -demuxer rawvideo -rawvideo w=1280:h=720 -loop 0 -fps 30
mplayer 2.yuv -demuxer rawvideo -rawvideo w=640:h=360 -loop 0 -fps 30
mplayer 3.yuv -demuxer rawvideo -rawvideo w=320:h=180 -loop 0 -fps 30

The encoding parameters can be modified in vp8_multi_resolution_encoder.c,
for example, target bitrate, frame rate...

Modified API. John helped a lot with that. Thanks!

Change-Id: I03be9a51167eddf94399f92d269599fb3f3d54f5
2011-12-05 17:59:42 -05:00