From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D56A6C433E0 for ; Tue, 19 May 2020 06:53:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AC0A620758 for ; Tue, 19 May 2020 06:53:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=xs4all.nl header.i=@xs4all.nl header.b="L+oC/Jmj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728277AbgESGxQ (ORCPT ); Tue, 19 May 2020 02:53:16 -0400 Received: from lb3-smtp-cloud7.xs4all.net ([194.109.24.31]:58061 "EHLO lb3-smtp-cloud7.xs4all.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726841AbgESGxP (ORCPT ); Tue, 19 May 2020 02:53:15 -0400 Received: from cust-b5b5937f ([IPv6:fc0c:c16d:66b8:757f:c639:739b:9d66:799d]) by smtp-cloud7.xs4all.net with ESMTPA id aw7hj0Ey2tKAsaw7kjOvD7; Tue, 19 May 2020 08:53:13 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=xs4all.nl; s=s1; t=1589871193; bh=Ua/Rh1jOjXzr3/TuekSvHN/AoVWwSnLpt91fLWvkvRQ=; h=Subject:To:From:Message-ID:Date:MIME-Version:Content-Type:From: Subject; b=L+oC/Jmjh2cFpViFqxKFurLG7iiTd+9gLDUXeMbolCH4lXYIiL4ALwmyqG5EZLCnd 8mhpwp+PG3Y360zqPOMhNNm/Gc/sKxe5TKNbmwvNArCMiALAFKxNt5nVqC2Edu3gJN k4VCN1C6RoMeySee8kjvUHPA4RO2ho+cJXt5HflxHdAqof/RGTUi69aEbqncNsSd/k rqYk8diCyTv4GdgtSjHOsxAUu8AonrXXVveOhn3k/f91gDTG3jiF3daQJQ+uv42xRj UZb+gpEZpscL2SFm9um+jCYKy5GwAVeVi/zeLZk40OCZhxXx+B6fRrPyt76Yss2dS6 DdpPeaOPvW5aA== Subject: Re: [PATCH] media: v4l2-ctrls: add encoder skip frames control To: Maheshwar Ajja , mchehab@kernel.org, ezequiel@collabora.com, p.zabel@pengutronix.de, paul.kocialkowski@bootlin.com, jonas@kwiboo.se, posciak@chromium.org, boris.brezillon@collabora.com, ribalda@kernel.org, tglx@linutronix.de, sumitg@nvidia.com, linux-media@vger.kernel.org, linux-kernel@vger.kernel.org References: <1589853951-27948-1-git-send-email-majja@codeaurora.org> From: Hans Verkuil Message-ID: Date: Tue, 19 May 2020 08:53:09 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <1589853951-27948-1-git-send-email-majja@codeaurora.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-CMAE-Envelope: MS4wfBdGLGyDxqJBDhS4e1zv0v3mcuFZ3y4Tg1jyH0FDCqJs3x5d04ojQqEHC1xdyvODYpHRanzoCnfo6paJpmIeNZANOqQxM4a3CnU89qHsyoQcXYdPJyNt Bl+1zahgUy6nYGflF2HRpW1ZAzWclHG42GZD6BpD0MZ7Ytfzb9RmvBLbUt9NRNjvrG7aOmajIhRt9WVIzehFp2zCpZh+m3/Sp6q35+oTFdpO/ym5uc+VGkk5 z/svh8k3hj/xIzLgwOeROGqqMBkS9JK+5e0CvyC1s5THeJ9zT0ytRm6GPjTEMBZv1fbjCWr85XQcTxHLgvd4DFz8dooMvkRVhekw9DbA7TXixNn5hueez/Fe EKZAA38iBr7QrcdCpsSnOubQkRLgWNqU3QnhDOTzVmre3yMqxyd/p0Hwvgf6hc5sfZi9aOu+BSeXy9KYl8VSn8zIK1raV67KTNQRHfS4vHepglyI901jy3rG l6uG1HtZPeE1ez+Ua/0NdubrXpXXh4uEU8QPa5I5oEuggfjB8p6ycVrE34bOIWsBfWjCVcvPhwPtsSkL4zKo0Phz8tGc/1zJa7TSEn3xF/a0XMhZ2tYOCQOS LdQ= Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 19/05/2020 04:05, Maheshwar Ajja wrote: > If V4L2_CID_MPEG_VIDEO_ENC_SKIP_FRAMES control is enabled > encoder can drop frames, if required, to achieve target bitrate > instead of modifying the quantization parameter which lowers > the encoded frame quality. > > Reference: 4.3.8.1 OMX_Video_ControlRateConstantSkipFrames > https://www.khronos.org/registry/OpenMAX-IL/specs/OpenMAX_IL_1_1_2_Specification.pdf > > Signed-off-by: Maheshwar Ajja > --- > Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst | 7 +++++++ > drivers/media/v4l2-core/v4l2-ctrls.c | 2 ++ > include/uapi/linux/v4l2-controls.h | 1 + > 3 files changed, 10 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..bc9265d 100644 > --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst > +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst > @@ -1081,6 +1081,13 @@ enum v4l2_mpeg_video_h264_entropy_mode - > Macroblock level rate control enable. Applicable to the MPEG4 and > H264 encoders. > > +``V4L2_CID_MPEG_VIDEO_ENC_SKIP_FRAMES (boolean)`` > + Encoder skip frames enable. This control is applicable only if > + ``V4L2_CID_MPEG_VIDEO_BITRATE_MODE`` control is set. If this control > + is enabled encoder can drop frames, if required, to achieve target > + bitrate instead of modifying the quantization parameter which lowers > + the encoded frame quality. It's a bit unclear for which bitrate modes this control is valid: only for MODE_CBR, or also for the constant quality bitrate mode? Or both? The phrase 'control is set' is meaningless for a menu control: it really is always 'set'. So that needs to be reworked so it is more explicit. Also note that there is an Exynos MFC control that appears to do something similar: V4L2_CID_MPEG_MFC51_VIDEO_FRAME_SKIP_MODE. To what extent does that overlap with the functionality proposed here? It looks like this proposed control is basically the equivalent of setting V4L2_CID_MPEG_MFC51_VIDEO_FRAME_SKIP_MODE to V4L2_MPEG_MFC51_FRAME_SKIP_MODE_LEVEL_LIMIT. So perhaps this MFC control should be promoted to a standard MPEG control instead of inventing a new control? Regards, Hans > + > ``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..d2cb766 100644 > --- a/drivers/media/v4l2-core/v4l2-ctrls.c > +++ b/drivers/media/v4l2-core/v4l2-ctrls.c > @@ -914,6 +914,7 @@ const char *v4l2_ctrl_get_name(u32 id) > case V4L2_CID_MPEG_VIDEO_FWHT_PARAMS: return "FWHT Stateless Parameters"; > case V4L2_CID_FWHT_I_FRAME_QP: return "FWHT I-Frame QP Value"; > case V4L2_CID_FWHT_P_FRAME_QP: return "FWHT P-Frame QP Value"; > + case V4L2_CID_MPEG_VIDEO_ENC_SKIP_FRAMES: return "Encoder Skip Frames"; > > /* VPX controls */ > case V4L2_CID_MPEG_VIDEO_VPX_NUM_PARTITIONS: return "VPX Number of Partitions"; > @@ -1180,6 +1181,7 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type, > case V4L2_CID_MPEG_VIDEO_DECODER_SLICE_INTERFACE: > case V4L2_CID_MPEG_VIDEO_FRAME_RC_ENABLE: > case V4L2_CID_MPEG_VIDEO_MB_RC_ENABLE: > + case V4L2_CID_MPEG_VIDEO_ENC_SKIP_FRAMES: > case V4L2_CID_MPEG_VIDEO_H264_8X8_TRANSFORM: > case V4L2_CID_MPEG_VIDEO_H264_VUI_SAR_ENABLE: > case V4L2_CID_MPEG_VIDEO_MPEG4_QPEL: > diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h > index 0ba1005..d3bc015 100644 > --- a/include/uapi/linux/v4l2-controls.h > +++ b/include/uapi/linux/v4l2-controls.h > @@ -742,6 +742,7 @@ 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_ENC_SKIP_FRAMES (V4L2_CID_MPEG_BASE + 645) > > /* MPEG-class control IDs specific to the CX2341x driver as defined by V4L2 */ > #define V4L2_CID_MPEG_CX2341X_BASE (V4L2_CTRL_CLASS_MPEG | 0x1000) >