From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 476D9488D86; Thu, 24 Sep 2026 20:46:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.251.105.195 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790282810; cv=none; b=Fc3JrKqAfzUnkfvqV0vYaW38K6iMjelWDvTGOcQr3eKQC5EwyNe1lAgDTjg72s+Qx1UrLrJ2KSEVoWLXOzw7hus6rPqZgPATu6UxJMWdzXBWwtymPXbn0/0YT2wS/+dvcXMgTDTixMKD7y+nGpVnov7w0exfdvO35PXaSAUvORU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790282810; c=relaxed/simple; bh=ZxkrPL30PUD8vP5ntlrp+qcubhHME4v9ZvuZDwUuoSE=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=sR4ZZlzhAQxMRZNhF8hrcML+t6D4j26w0o53CLX/C1wY4BHUWFTntoe1fCCAM52vy6kprNDK2taXmgFnmBbCXoeOPpPk2CiB1cDAg60l7J/59/eTu5Eq4zGKAltOIrUH2jsojC+S5PrUK272FYJMrSSLTPiIAvE+BZRVmoDYrJM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b=GCLkaPvw; arc=none smtp.client-ip=148.251.105.195 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="GCLkaPvw" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1790282807; bh=ZxkrPL30PUD8vP5ntlrp+qcubhHME4v9ZvuZDwUuoSE=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=GCLkaPvwThqg/tLIC1YahbDhGK2z+k4HSMwRd2ltI+5QxU/yAI0gRUgJLu+DwrPYe IKFD/Zggp6EBBDYZ2vMEe9g/QroSDDSO2CMZvQ1mUazBS+QIA4Pw9zNspISP0I9jJ5 n9RhqQEWIJ9aPeYhc4SLCAnTmqzM0JNGrfibrLU5FzpaELewDs1mzGGsPdfjxussD7 g43P+fb7LQkWGzrfAwVdpt31cm7XS4PgfAgPON+d/uAtldU3NkeTA/kHdjazBy/f3b m54YznAUNrLqq/4OKayvzkK/v1pC71aiJ3sbwHacNebmNQSqanWxchPcIoC2z7T4SB l/wYliqk171UA== Received: from [100.64.0.214] (unknown [100.64.0.214]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange secp256r1 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: nicolas) by bali.collaboradmins.com (Postfix) with ESMTPSA id 4E4D917E01C5; Thu, 24 Sep 2026 22:46:45 +0200 (CEST) Message-ID: <013b1e7ceb7cf046888109631e72ce4c408ab88a.camel@collabora.com> Subject: Re: [PATCH 00/14] media: Add V4L2 H.264 stateless encode and VC8000E support From: Nicolas Dufresne To: Paul Kocialkowski Cc: Michael Nazzareno Trimarchi , devicetree , "open list:FREESCALE IMX / MXC FEC DRIVER" , linux-arm-kernel , LKML , linux-media , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Benjamin Gaignard , Philipp Zabel , Mauro Carvalho Chehab , Hans Verkuil , Marco Felsch , Michael Tretter Date: Thu, 24 Sep 2026 16:46:43 -0400 In-Reply-To: References: <20260522101653.2565125-1-paulk@sys-base.io> <48271d518bb25f552309de12758e9a9995905f0c.camel@collabora.com> Autocrypt: addr=nicolas.dufresne@collabora.com; prefer-encrypt=mutual; keydata=mDMEaCN2ixYJKwYBBAHaRw8BAQdAM0EHepTful3JOIzcPv6ekHOenE1u0vDG1gdHFrChD /e0J05pY29sYXMgRHVmcmVzbmUgPG5pY29sYXNAbmR1ZnJlc25lLmNhPoicBBMWCgBEAhsDBQsJCA cCAiICBhUKCQgLAgQWAgMBAh4HAheABQkJZfd1FiEE7w1SgRXEw8IaBG8S2UGUUSlgcvQFAmibrjo CGQEACgkQ2UGUUSlgcvQlQwD/RjpU1SZYcKG6pnfnQ8ivgtTkGDRUJ8gP3fK7+XUjRNIA/iXfhXMN abIWxO2oCXKf3TdD7aQ4070KO6zSxIcxgNQFtDFOaWNvbGFzIER1ZnJlc25lIDxuaWNvbGFzLmR1Z nJlc25lQGNvbGxhYm9yYS5jb20+iJkEExYKAEECGwMFCwkIBwICIgIGFQoJCAsCBBYCAwECHgcCF4 AWIQTvDVKBFcTDwhoEbxLZQZRRKWBy9AUCaCyyxgUJCWX3dQAKCRDZQZRRKWBy9ARJAP96pFmLffZ smBUpkyVBfFAf+zq6BJt769R0al3kHvUKdgD9G7KAHuioxD2v6SX7idpIazjzx8b8rfzwTWyOQWHC AAS0LU5pY29sYXMgRHVmcmVzbmUgPG5pY29sYXMuZHVmcmVzbmVAZ21haWwuY29tPoiZBBMWCgBBF iEE7w1SgRXEw8IaBG8S2UGUUSlgcvQFAmibrGYCGwMFCQll93UFCwkIBwICIgIGFQoJCAsCBBYCAw ECHgcCF4AACgkQ2UGUUSlgcvRObgD/YnQjfi4+L8f4fI7p1pPMTwRTcaRdy6aqkKEmKsCArzQBAK8 bRLv9QjuqsE6oQZra/RB4widZPvphs78H0P6NmpIJ Organization: Collabora Canada Content-Type: multipart/signed; micalg="pgp-sha512"; protocol="application/pgp-signature"; boundary="=-RZqRkCQcXHsSV3m7pcT/" User-Agent: Evolution 3.60.2 (3.60.2-1.fc44) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 --=-RZqRkCQcXHsSV3m7pcT/ Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Paul [...] > By the way if you have ideas about specific problems with the stateful > API that should not be reproduced in the stateless one, feel free to > mention them. Few things: - Drain flow should be as simple as for stateless decoder, there is no reordering, and so no holding on frames. - Capability query should mimic the stateless decoders (but up-side down). Basically, we don't add a pseudo unset state, that was bogus. V4L2_FMTDESC_FLAG_ENUM_ALL could be made mandatory, this is only partially implemented decoders today :-S - Capture/Output S_PARM, maybe review/revisit, but likely still needed, otherwise the rate controller can't know the rate. - S_SELECTION, maybe make it mandatory for codec with a conformance window = ? - Of course, encoding process requires a request - Anything about keyframe insertion can be dropped, since frame type is exp= licit and per codec. One ambiguity we have in all decoders at least is weather or not the enumer= ate sized are coded or display resolution. I believe technically, all stateless decoder exposes constraints in coded resolutions, and display resolutions a= re not easily enumerated. Not a blocker, just a remark. Hope this is helpful, Nicolas >=20 > > A second implementation, not just a variant of the same brand would als= o be > > nice. >=20 > I still have it in mind to add support for the Allwinner encoder based > on my earlier stateful-ish attempt. Hopefully that work can be funded. >=20 > All the best, >=20 > Paul --=-RZqRkCQcXHsSV3m7pcT/ Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTvDVKBFcTDwhoEbxLZQZRRKWBy9AUCarWMMwAKCRDZQZRRKWBy 9NqWAP42EmwEZYXkDrrIHimfO2YkL1gxjjiSxbQmMV+aniWsxQEApmExmBL7mmz6 RyLWV0kcepV0pLiYo5RAuCDOTzACyQA= =26C6 -----END PGP SIGNATURE----- --=-RZqRkCQcXHsSV3m7pcT/--