Hi Tomasz,
On 11/3/18 5:01 AM, Tomasz Figa wrote:
> Hi Malathi,
>
> On Fri, Nov 2, 2018 at 9:58 PM Malathi Gottam <mgottam@xxxxxxxxxxxxxx> wrote:
>>
>> When client requests for a keyframe, set the property
>> to hardware to generate the sync frame.
>>
>> Signed-off-by: Malathi Gottam <mgottam@xxxxxxxxxxxxxx>
>> ---
>> drivers/media/platform/qcom/venus/venc_ctrls.c | 20 +++++++++++++++++++-
>> 1 file changed, 19 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/media/platform/qcom/venus/venc_ctrls.c b/drivers/media/platform/qcom/venus/venc_ctrls.c
>> index 45910172..59fe7fc 100644
>> --- a/drivers/media/platform/qcom/venus/venc_ctrls.c
>> +++ b/drivers/media/platform/qcom/venus/venc_ctrls.c
>> @@ -79,8 +79,10 @@ static int venc_op_s_ctrl(struct v4l2_ctrl *ctrl)
>> {
>> struct venus_inst *inst = ctrl_to_inst(ctrl);
>> struct venc_controls *ctr = &inst->controls.enc;
>> + struct hfi_enable en = { .enable = 1 };
>> u32 bframes;
>> int ret;
>> + u32 ptype;
>>
>> switch (ctrl->id) {
>> case V4L2_CID_MPEG_VIDEO_BITRATE_MODE:
>> @@ -173,6 +175,19 @@ static int venc_op_s_ctrl(struct v4l2_ctrl *ctrl)
>>
>> ctr->num_b_frames = bframes;
>> break;
>> + case V4L2_CID_MPEG_VIDEO_FORCE_KEY_FRAME:
>> + mutex_lock(&inst->lock);
>> + if (inst->streamon_out && inst->streamon_cap) {
>
> We had a discussion on this in v2. I don't remember seeing any conclusion.
>
> Obviously the hardware should generate a keyframe naturally when the
> CAPTURE streaming starts, which is where the encoding starts, but the
> state of the OUTPUT queue should not affect this.
>
> The application is free to stop and start streaming on the OUTPUT
> queue as it goes and it shouldn't imply any side effects in the
> encoded bitstream (e.g. a keyframe inserted). So:
> - a sequence of STREAMOFF(OUTPUT),
> S_CTRL(V4L2_CID_MPEG_VIDEO_FORCE_KEY_FRAME), STREAMON(OUTPUT) should
> explicitly generate a keyframe,
I agree with you, but presently we don't follow strictly the stateful
encoder spec. In this spirit I think proposed patch is applicable to the
current state of the encoder driver, and your comment should be
addressed in the follow-up patches where we have to re-factor a bit
start/stop_streaming according to the encoder documentation.
But until then we have to get that patch.
> - a sequence of STREAMOFF(OUTPUT), STREAMON(OUTPUT) should _not_
> explicitly generate a keyframe (the hardware may generate one, if the
> periodic keyframe counter is active or a scene detection algorithm
> decides so).
>
> Please refer to the specification (v2 is the latest for the time being
> -> https://lore.kernel.org/patchwork/patch/1002476/) for further
> details and feel free to leave any comment for it.
>
> Best regards,
> Tomasz
>
--
regards,
Stan
