Messages in this thread | | | Date | Thu, 11 Mar 2021 16:45:48 +0530 | From | dikshita@codeauro ... | Subject | Re: [PATCH v7 1/2] media: v4l2-ctrl: add controls for long term reference. |
| |
Hi Hans,
Thanks for your comments. I Will update the documentation based on your suggestion in the next patch.
Thanks, Dikshita
On 2021-03-05 14:08, Hans Verkuil wrote: > Hi Dikshita, > > On 03/03/2021 12:09, Dikshita Agarwal wrote: >> Long Term Reference (LTR) frames are the frames that are encoded >> sometime in the past and stored in the DPB buffer list to be used >> as reference to encode future frames. >> This change adds controls to enable this feature. >> >> Signed-off-by: Dikshita Agarwal <dikshita@codeaurora.org> >> --- >> .../userspace-api/media/v4l/ext-ctrls-codec.rst | 17 >> +++++++++++++++++ >> drivers/media/v4l2-core/v4l2-ctrls.c | 14 >> ++++++++++++++ >> include/uapi/linux/v4l2-controls.h | 3 +++ >> 3 files changed, 34 insertions(+) >> >> diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst >> b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst >> index 00944e9..21fa9a5 100644 >> --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst >> +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst >> @@ -3646,3 +3646,20 @@ enum v4l2_mpeg_video_hevc_size_of_length_field >> - >> so this has to come from client. >> This is applicable to H264 and valid Range is from 0 to 63. >> Source Rec. ITU-T H.264 (06/2019); G.7.4.1.1, G.8.8.1. >> + >> +``V4L2_CID_MPEG_VIDEO_LTR_COUNT (integer)`` >> + Specifies the maximum number of Long Term Reference (LTR) frames >> at any >> + given time that the encoder can keep. >> + This is applicable to the H264 and HEVC encoders. >> + >> +``V4L2_CID_MPEG_VIDEO_FRAME_LTR_INDEX (integer)`` >> + The current frame is marked as a Long Term Reference (LTR) frame > > You mentioned earlier in a reply to me that: > > "The driver implementation ensures that whenever the LTR control is > received, it applies to the frame received after that. Not to frame > which would be > encoded next." > > That behavior is not clear from the text. > > Wouldn't this be a better text: > > "After setting this control the frame that will be queued next > will be marked as a Long Term Reference (LTR) frame" > > "current frame" isn't precise enough. > >> + and given this LTR index which ranges from 0 to LTR_COUNT-1. >> + This is applicable to the H264 and HEVC encoders. >> + Source Rec. ITU-T H.264 (06/2019); Table 7.9 >> + >> +``V4L2_CID_MPEG_VIDEO_USE_LTR_FRAMES (bitmask)`` >> + Specifies the Long Term Reference (LTR) frame(s) to be used for >> + encoding the current frame. > > Same here. I assume that here too this control applies to the next > queued > frame. > >> + This provides a bitmask which consists of bits [0, LTR_COUNT-1]. >> + This is applicable to the H264 and HEVC encoders. > > Regards, > > Hans > >> diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c >> b/drivers/media/v4l2-core/v4l2-ctrls.c >> index 016cf62..4d444de 100644 >> --- a/drivers/media/v4l2-core/v4l2-ctrls.c >> +++ b/drivers/media/v4l2-core/v4l2-ctrls.c >> @@ -951,6 +951,9 @@ const char *v4l2_ctrl_get_name(u32 id) >> case V4L2_CID_MPEG_VIDEO_REPEAT_SEQ_HEADER: return "Repeat Sequence >> Header"; >> case V4L2_CID_MPEG_VIDEO_FORCE_KEY_FRAME: return "Force Key Frame"; >> case V4L2_CID_MPEG_VIDEO_BASELAYER_PRIORITY_ID: return "Base Layer >> Priority ID"; >> + case V4L2_CID_MPEG_VIDEO_LTR_COUNT: return "LTR Count"; >> + case V4L2_CID_MPEG_VIDEO_FRAME_LTR_INDEX: return "Frame LTR Index"; >> + case V4L2_CID_MPEG_VIDEO_USE_LTR_FRAMES: return "Use LTR Frames"; >> case V4L2_CID_MPEG_VIDEO_MPEG2_SLICE_PARAMS: return "MPEG-2 Slice >> Parameters"; >> case V4L2_CID_MPEG_VIDEO_MPEG2_QUANTIZATION: return "MPEG-2 >> Quantization Matrices"; >> case V4L2_CID_FWHT_I_FRAME_QP: return "FWHT I-Frame QP Value"; >> @@ -1278,6 +1281,17 @@ void v4l2_ctrl_fill(u32 id, const char **name, >> enum v4l2_ctrl_type *type, >> case V4L2_CID_MPEG_VIDEO_MV_V_SEARCH_RANGE: >> *type = V4L2_CTRL_TYPE_INTEGER; >> break; >> + case V4L2_CID_MPEG_VIDEO_LTR_COUNT: >> + *type = V4L2_CTRL_TYPE_INTEGER; >> + break; >> + case V4L2_CID_MPEG_VIDEO_FRAME_LTR_INDEX: >> + *type = V4L2_CTRL_TYPE_INTEGER; >> + *flags |= V4L2_CTRL_FLAG_EXECUTE_ON_WRITE; >> + break; >> + case V4L2_CID_MPEG_VIDEO_USE_LTR_FRAMES: >> + *type = V4L2_CTRL_TYPE_BITMASK; >> + *flags |= V4L2_CTRL_FLAG_EXECUTE_ON_WRITE; >> + break; >> case V4L2_CID_MPEG_VIDEO_FORCE_KEY_FRAME: >> case V4L2_CID_PAN_RESET: >> case V4L2_CID_TILT_RESET: >> diff --git a/include/uapi/linux/v4l2-controls.h >> b/include/uapi/linux/v4l2-controls.h >> index 039c0d7..fedbb54 100644 >> --- a/include/uapi/linux/v4l2-controls.h >> +++ b/include/uapi/linux/v4l2-controls.h >> @@ -428,6 +428,9 @@ enum v4l2_mpeg_video_multi_slice_mode { >> #define >> V4L2_CID_MPEG_VIDEO_MV_V_SEARCH_RANGE (V4L2_CID_CODEC_BASE+228) >> #define >> V4L2_CID_MPEG_VIDEO_FORCE_KEY_FRAME (V4L2_CID_CODEC_BASE+229) >> #define >> V4L2_CID_MPEG_VIDEO_BASELAYER_PRIORITY_ID (V4L2_CID_CODEC_BASE+230) >> +#define V4L2_CID_MPEG_VIDEO_LTR_COUNT (V4L2_CID_CODEC_BASE+231) >> +#define >> V4L2_CID_MPEG_VIDEO_FRAME_LTR_INDEX (V4L2_CID_CODEC_BASE+232) >> +#define V4L2_CID_MPEG_VIDEO_USE_LTR_FRAMES (V4L2_CID_CODEC_BASE+233) >> >> /* CIDs for the MPEG-2 Part 2 (H.262) codec */ >> #define V4L2_CID_MPEG_VIDEO_MPEG2_LEVEL (V4L2_CID_CODEC_BASE+270) >>
| |