Hi Maheshwar,
On 18/05/2020 23:09, [email protected] wrote:
> Hi,
>
> Regarding below patch -
>
> HEIF/HEIC image encoding uses HEVC/AVC encoders and client can set image
> quality level using
> V4L2_CID_MPEG_VIDEO_FRAME_QUALITY control.
>
> Reference BITRATE_MODE_CQ at
> https://developer.android.com/reference/android/media/MediaCodecInfo.EncoderCapabilities#BITRATE_MODE_CQ
So what you are really introducing here is a new enum
v4l2_mpeg_video_bitrate_mode
mode: V4L2_MPEG_VIDEO_BITRATE_MODE_CQ.
Why not just add that new mode, then add V4L2_CID_MPEG_VIDEO_CONSTANT_QUALITY
which is only used if the bitrate mode is MODE_CQ.
That builds nicely on top of the already existing
V4L2_CID_MPEG_VIDEO_BITRATE_MODE
control.
Regards,
Hans
>
> Regards,
> Maheshwar.
>
>
> On 2020-05-18 14:07, Maheshwar Ajja wrote:
>> When frame quality control is enabled encoder will choose
>> the appropriate quantization parameter and bitrate to
>> produce the client requested frame quality level.
>> When frame quality control is disabled then frame quality
>> is decided based on appropriate controls (i.e.
>> V4L2_CID_MPEG_VIDEO_FRAME_RC_ENABLE and/or
>> V4L2_CID_MPEG_VIDEO_BITRATE_MODE)
>>
>> Signed-off-by: Maheshwar Ajja <[email protected]>
>> ---
>> .../userspace-api/media/v4l/ext-ctrls-codec.rst | 16
>> ++++++++++++++++
>> drivers/media/v4l2-core/v4l2-ctrls.c | 3 +++
>> include/uapi/linux/v4l2-controls.h | 2 ++
>> 3 files changed, 21 insertions(+)
>>
>> diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
>> b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
>> index d0d506a..495b39b 100644
>> --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
>> +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
>> @@ -1081,6 +1081,22 @@ enum v4l2_mpeg_video_h264_entropy_mode -
>> Macroblock level rate control enable. Applicable to the MPEG4 and
>> H264 encoders.
>>
>> +``V4L2_CID_MPEG_VIDEO_FRAME_QUALITY_ENABLE (boolean)``
>> + Encoded frame quality control enable. If this control is enabled
>> then
>> + the quality level of the encoded frame is set with control
>> + ``V4L2_CID_MPEG_VIDEO_CONSTANT_QUALITY``. If this control is
>> disabled
>> + then the quality level of encoded frame is adjusted with
>> appropriate
>> + controls (e.g. ``V4L2_CID_MPEG_VIDEO_FRAME_RC_ENABLE`` or
>> + ``V4L2_CID_MPEG_VIDEO_BITRATE_MODE``). Applicable to encoders.
>> +
>> +``V4L2_CID_MPEG_VIDEO_FRAME_QUALITY (integer)``
>> + Encoded frame quality control. If the control
>> + ``V4L2_CID_MPEG_VIDEO_FRAME_QUALITY_ENABLE`` is enabled then the
>> + quality of encoded frame is set with this control. Valid range is
>> 1 to
>> + 100 where 1 indicates lowest quality and 100 indicates highest
>> quality.
>> + Encoder will decide the appropriate quantization parameter and
>> bitrate
>> + to produce requested frame quality. Applicable to encoders.
>> +
>> ``V4L2_CID_MPEG_VIDEO_MPEG4_QPEL (boolean)``
>> Quarter pixel motion estimation for MPEG4. Applicable to the MPEG4
>> encoder.
>> diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c
>> b/drivers/media/v4l2-core/v4l2-ctrls.c
>> index 1c617b4..1477198 100644
>> --- a/drivers/media/v4l2-core/v4l2-ctrls.c
>> +++ b/drivers/media/v4l2-core/v4l2-ctrls.c
>> @@ -982,6 +982,8 @@ const char *v4l2_ctrl_get_name(u32 id)
>> case V4L2_CID_MPEG_VIDEO_HEVC_SLICE_PARAMS: return "HEVC
>> Slice
>> Parameters";
>> case V4L2_CID_MPEG_VIDEO_HEVC_DECODE_MODE: return "HEVC
>> Decode
>> Mode";
>> case V4L2_CID_MPEG_VIDEO_HEVC_START_CODE: return "HEVC
>> Start Code";
>> + case V4L2_CID_MPEG_VIDEO_FRAME_QUALITY_ENABLE: return "Frame
>> Quality
>> Enable";
>> + case V4L2_CID_MPEG_VIDEO_FRAME_QUALITY: return "Frame
>> Quality";
>>
>> /* CAMERA controls */
>> /* Keep the order of the 'case's the same as in v4l2-controls.h! */
>> @@ -1178,6 +1180,7 @@ void v4l2_ctrl_fill(u32 id, const char **name,
>> enum v4l2_ctrl_type *type,
>> case V4L2_CID_FLASH_READY:
>> case V4L2_CID_MPEG_VIDEO_DECODER_MPEG4_DEBLOCK_FILTER:
>> case V4L2_CID_MPEG_VIDEO_DECODER_SLICE_INTERFACE:
>> + case V4L2_CID_MPEG_VIDEO_FRAME_QUALITY_ENABLE:
>> case V4L2_CID_MPEG_VIDEO_FRAME_RC_ENABLE:
>> case V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE:
>> case V4L2_CID_MPEG_VIDEO_H264_8X8_TRANSFORM:
>> diff --git a/include/uapi/linux/v4l2-controls.h
>> b/include/uapi/linux/v4l2-controls.h
>> index 0ba1005..d97a934 100644
>> --- a/include/uapi/linux/v4l2-controls.h
>> +++ b/include/uapi/linux/v4l2-controls.h
>> @@ -742,6 +742,8 @@ enum v4l2_cid_mpeg_video_hevc_size_of_length_field
>> {
>> #define V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L6_BR (V4L2_CID_MPEG_BASE
>> + 642)
>> #define V4L2_CID_MPEG_VIDEO_REF_NUMBER_FOR_PFRAMES (V4L2_CID_MPEG_BASE
>> + 643)
>> #define V4L2_CID_MPEG_VIDEO_PREPEND_SPSPPS_TO_IDR (V4L2_CID_MPEG_BASE
>> + 644)
>> +#define V4L2_CID_MPEG_VIDEO_FRAME_QUALITY_ENABLE (V4L2_CID_MPEG_BASE +
>> 645)
>> +#define V4L2_CID_MPEG_VIDEO_FRAME_QUALITY (V4L2_CID_MPEG_BASE +
>> 646)
>>
>> /* MPEG-class control IDs specific to the CX2341x driver as defined
>> by V4L2 */
>> #define V4L2_CID_MPEG_CX2341X_BASE
>> (V4L2_CTRL_CLASS_MPEG | 0x1000)
