Merge "Describe Video Encoding Floor" into sc-dev am: 11badea7 am: b3695ff5

 Finally, you request (or receive) a filled output buffer, consume its contents and release it

 back to the codec.

 <h3 id=qualityFloor><a name="qualityFloor">Minimum Quality Floor for Video Encoding</h3>

 <p>

 Beginning with {@link android.os.Build.VERSION_CODES#S}, Android's Video MediaCodecs enforce a

 minimum quality floor. The intent is to eliminate poor quality video encodings. This quality

 floor is applied when the codec is in Variable Bitrate (VBR) mode; it is not applied when

 the codec is in Constant Bitrate (CBR) mode. The quality floor enforcement is also restricted

 to a particular size range; this size range is currently for video resolutions

 larger than 320x240 up through 1920x1080.

 <p>

 When this quality floor is in effect, the codec and supporting framework code will work to

 ensure that the generated video is of at least a "fair" or "good" quality. The metric

 used to choose these targets is the VMAF (Video Multi-method Assessment Function) with a

 target score of 70 for selected test sequences.

 <p>

 The typical effect is that

 some videos will generate a higher bitrate than originally configured. This will be most

 notable for videos which were configured with very low bitrates; the codec will use a bitrate

 that is determined to be more likely to generate an "fair" or "good" quality video. Another

 situation is where a video includes very complicated content (lots of motion and detail);

 in such configurations, the codec will use extra bitrate as needed to avoid losing all of

 the content's finer detail.

 <p>

 This quality floor will not impact content captured at high bitrates (a high bitrate should

 already provide the codec with sufficient capacity to encode all of the detail).

 The quality floor does not operate on CBR encodings.

 The quality floor currently does not operate on resolutions of 320x240 or lower, nor on

 videos with resolution above 1920x1080.

 <h3>Data Types</h3>

 <p>

 Codecs operate on three kinds of data: compressed data, raw audio data and raw video data.

     * clipped internally to ensure the video recording can proceed smoothly based on

     * the capabilities of the platform.

     *

     * <p>

     * NB: the actual bitrate and other encoding characteristics may be affected by

     * the minimum quality floor behavior introduced in

     * {@link android.os.Build.VERSION_CODES#S}. More detail on how and where this

     * impacts video encoding can be found in the

     * {@link MediaCodec} page and looking for "quality floor" (near the top of the page).

     *

     * @param bitRate the video encoding bit rate in bits per second.

     */

    public void setVideoEncodingBitRate(int bitRate) {