.. SPDX-License-Identifier: CC-BY-SA-4.0 IPA Writer's Guide ================== IPA modules are Image Processing Algorithm modules. They provide functionality that the pipeline handler can use for image processing. This guide covers the definition of the IPA interface, and how to plumb the connection between the pipeline handler and the IPA. The IPA interface and protocol ------------------------------ The IPA interface defines the interface between the pipeline handler and the IPA. Specifically, it defines the functions that the IPA exposes that the pipeline handler can call, and the signals that the pipeline handler can connect to, in order to receive data from the IPA asynchronously. In addition, it contains any custom data structures that the pipeline handler and IPA may pass to each other. The IPA protocol refers to the agreement between the pipeline handler and the IPA regarding the expected response(s) from the IPA for given calls to the IPA. This protocol doesn't need to be declared anywhere in code, but it shall be documented, as there may be multiple IPA implementations for one pipeline handler. As part of the design of libcamera, IPAs may be isolated in a separate process, or run in the same process but a different thread from libcamera. The pipeline handler and IPA shall not have to change their operation based on whether the IPA is isolated or not, but the possibility of isolation needs to be kept in mind. Therefore all data that is passed between them must be serializable, so they must be defined separately in the `mojo Interface Definition Language`_ (IDL), and a code generator will generate headers and serializers corresponding to the definitions. Every interface is defined in a mojom file and includes: - the functions that the pipeline handler can call from the IPA - signals in the pipeline handler that the IPA can emit - any data structures that are to be passed between the pipeline handler and the IPA All IPA modules of a given pipeline handler use the same IPA interface. The IPA interface definition is thus written by the pipeline handler author, based on how they design the interactions between the pipeline handler and the IPA. The entire IPA interface, including the functions, signals, and any custom structs shall be defined in a file named {pipeline_name}.mojom under include/libcamera/ipa/. .. _mojo Interface Definition Language: https://chromium.googlesource.com/chromium/src.git/+/master/mojo/public/tools/bindings/README.md Namespacing ----------- To avoid name collisions between data types defined by different IPA interfaces and data types defined by libcamera, each IPA interface must be defined in its own namespace. The namespace is specific with mojo's module directive. It must be the first non-comment line in the mojo data definition file. For example, the Raspberry Pi IPA interface uses: .. code-block:: none module ipa.rpi; This will become the ipa::rpi namespace in C++ code. Data containers --------------- Since the data passed between the pipeline handler and the IPA must support serialization, any custom data containers must be defined with the mojo IDL. The following list of libcamera objects are supported in the interface definition, and may be used as function parameter types or struct field types: - libcamera.ControlInfoMap - libcamera.ControlList - libcamera.FileDescriptor - libcamera.IPABuffer - libcamera.IPACameraSensorInfo - libcamera.IPASettings - libcamera.IPAStream - libcamera.Point - libcamera.Rectangle - libcamera.Size - libcamera.SizeRange To use them, core.mojom must be included in the mojo data definition file: .. code-block:: none import "include/libcamera/ipa/core.mojom"; Other custom structs may be defined and used as well. There is no requirement that they must be defined before usage. enums and structs are supported. The following is an example of a definition of an enum, for the purpose of being used as flags: .. code-block:: none enum ConfigParameters { ConfigLsTable = 0x01, ConfigStaggeredWrite = 0x02, ConfigSensor = 0x04, ConfigDropFrames = 0x08, }; The following is an example of a definition of a struct: .. code-block:: none struct ConfigInput { uint32 op; uint32 transform; libcamera.FileDescriptor lsTableHandle; int32 lsTableHandleStatic = -1; map streamConfig; array buffers; }; This example has some special things about it. First of all, it uses the FileDescriptor data type. This type must be used to ensure that the file descriptor that it contains is translated properly across the IPC boundary (when the IPA is in an isolated process). This does mean that if the file descriptor should be sent without being translated (for example, for the IPA to tell the pipeline handler which fd *that the pipeline handler holds* to act on), then it must be in a regular int32 type. This example also illustrates that struct fields may have default values, as is assigned to lsTableHandleStatic. This is the value that the field will take when the struct is constructed with the default constructor. Arrays and maps are supported as well. They are translated to C++ vectors and maps, respectively. The members of the arrays and maps are embedded, and cannot be const. Note that nullable fields, static-length arrays, handles, and unions, which are supported by mojo, are not supported by our code generator. The Main IPA interface ---------------------- The IPA interface is split in two parts, the Main IPA interface, which describes the functions that the pipeline handler can call from the IPA, and the Event IPA interface, which describes the signals received by the pipeline handler that the IPA can emit. Both must be defined. This section focuses on the Main IPA interface. The main interface must be named as IPA{pipeline_name}Interface. The functions that the pipeline handler can call from the IPA may be synchronous or asynchronous. Synchronous functions do not return until the IPA returns from the function, while asynchronous functions return immediately without waiting for the IPA to return. At a minimum, the following three functions must be present (and implemented): - init(); - start(); - stop(); All three of these functions are synchronous. The parameters for start() and init() may be customized. init() initializes the IPA interface. It shall be called before any other function of the IPAInterface. stop() informs the IPA module that the camera is stopped. The IPA module shall release resources prepared in start(). A configure() method is recommended. Any ControlInfoMap instances that will be used by the IPA must be sent to the IPA from the pipeline handler, at configure time, for example. All input parameters will become const references, except for arithmetic types, which will be passed by value. Output parameters will become pointers, unless the first output parameter is an int32, or there is only one primitive output parameter, in which case it will become a regular return value. const is not allowed inside of arrays and maps. mojo arrays will become C++ std::vector<>. By default, all methods defined in the main interface are synchronous. This means that in the case of IPC (i.e. isolated IPA), the function call will not return until the return value or output parameters are ready. To specify an asynchronous function, the [async] attribute can be used. Asynchronous methods must not have any return value or output parameters, since in the case of IPC the call needs to return immediately. It is also possible that the IPA will not be run in isolation. In this case, the IPA thread will not exist until start() is called. This means that in the case of no isolation, asynchronous calls cannot be made before start(). Since the IPA interface must be the same regardless of isolation, the same restriction applies to the case of isolation, and any function that will be called before start() must be synchronous. In addition, any call made after start() and before stop() must be asynchronous. The motivation for this is to avoid damaging real-time performance of the pipeline handler. If the pipeline handler wants some data from the IPA, the IPA should return the data asynchronously via an event (see "The Event IPA interface"). The following is an example of a main interface definition: .. code-block:: none interface IPARPiInterface { init(libcamera.IPASettings settings, string sensorName) => (int32 ret, bool metadataSupport); start() => (int32 ret); stop(); configure(libcamera.IPACameraSensorInfo sensorInfo, map streamConfig, map entityControls, ConfigInput ipaConfig) => (int32 ret, ConfigOutput results); mapBuffers(array buffers); unmapBuffers(array ids); [async] signalStatReady(uint32 bufferId); [async] signalQueueRequest(libcamera.ControlList controls); [async] signalIspPrepare(ISPConfig data); }; The first three functions are the required functions. Functions do not need to have return values, like stop(), mapBuffers(), and unmapBuffers(). In the case of asynchronous functions, as explained before, they *must not* have return values. The Event IPA interface ----------------------- The event IPA interface describes the signals received by the pipeline handler that the IPA can emit. It must be defined. If there are no event functions, then it may be empty. These emissions are meant to notify the pipeline handler of some event, such as request data is ready, and *must not* be used to drive the camera pipeline from the IPA. The event interface must be named as IPA{pipeline_name}EventInterface. Methods defined in the event interface are implicitly asynchronous. Thus they cannot return any value. Specifying the [async] tag is not necessary. Methods defined in the event interface will become signals in the IPA interface. The IPA can emit signals, while the pipeline handler can connect slots to them. The following is an example of an event interface definition: .. code-block:: none interface IPARPiEventInterface { statsMetadataComplete(uint32 bufferId, libcamera.ControlList controls); runIsp(uint32 bufferId); embeddedComplete(uint32 bufferId); setIsp(libcamera.ControlList controls); setStaggered(libcamera.ControlList controls); }; Compiling the IPA interface --------------------------- After the IPA interface is defined in include/libcamera/ipa/{pipeline_name}.mojom, an entry for it must be added in meson so that it can be compiled. The filename must be added to the ipa_mojom_files object in include/libcamera/ipa/meson.build. For example, adding the raspberrypi.mojom file to meson: .. code-block:: none ipa_mojom_files = [ 'raspberrypi.mojom', ] This will cause the mojo data definition file to be compiled. Specifically, it generates five files: - a header describing the custom data structures, and the complete IPA interface (at {$build_dir}/include/libcamera/ipa/{pipeline}_ipa_interface.h) - a serializer implementing de/serialization for the custom data structures (at {$build_dir}/include/libcamera/ipa/{pipeline}_ipa_serializer.h) - a proxy header describing a specialized IPA proxy (at {$build_dir}/include/libcamera/ipa/{pipeline}_ipa_proxy.h) - a proxy source implementing the IPA proxy (at {$build_dir}/src/libcamera/proxy/{pipeline}_ipa_proxy.cpp) - a proxy worker source implementing the other end of the IPA proxy (at {$build_dir}/src/libcamera/proxy/worker/{pipeline}_ipa_proxy_worker.cpp) The IPA proxy serves as the layer between the pipeline handler and the IPA, and handles threading vs isolation transparently. The pipeline handler and the IPA only require the interface header and the proxy header. The serializer is only used internally by the proxy. Using the custom data structures -------------------------------- To use the custom data structures that are defined in the mojo data definition file, the following header must be included: .. code-block:: C++ #include The POD types of the structs simply become their C++ counterparts, eg. uint32 in mojo will become uint32_t in C++. mojo map becomes C++ std::map, and mojo array becomes C++ std::vector. All members of maps and vectors are embedded, and are not pointers. The members cannot be const. The names of all the fields of structs can be used in C++ in exactly the same way as they are defined in the data definition file. For example, the following struct as defined in the mojo file: .. code-block:: none struct SensorConfig { uint32 gainDelay = 1; uint32 exposureDelay; uint32 sensorMetadata; }; Will become this in C++: .. code-block:: C++ struct SensorConfig { uint32_t gainDelay; uint32_t exposureDelay; uint32_t sensorMetadata; }; The generated structs will also have two constructors, a constructor that fills all fields with the default values, and a second constructor that takes a value for every field. The default value constructor will fill in the fields with the specified default value if it exists. In the above example, `gainDelay_` will be initialized to 1. If no default value is specified, then it will be filled in as zero (or -1 for a FileDescriptor type). All fields and constructors/destructors in these generated structs are public. Using the IPA interface (pipeline handler) ------------------------------------------ The following headers are necessary to use an IPA in the pipeline handler (with raspberrypi as an example): .. code-block:: C++ #include #include The first header includes definitions of the custom data structures, and the definition of the complete IPA interface (including both the Main and the Event IPA interfaces). The name of the header file comes from the name of the mojom file, which in this case was raspberrypi.mojom. The second header includes the definition of the specialized IPA proxy. It exposes the complete IPA interface. We will see how to use it in this section. In the pipeline handler, we first need to construct a specialized IPA proxy. From the point of view of the pipeline hander, this is the object that is the IPA. To do so, we invoke the IPAManager: .. code-block:: C++ std::unique_ptr ipa_ = IPAManager::createIPA(pipe_, 1, 1); The ipa::rpi namespace comes from the namespace that we defined in the mojo data definition file, in the "Namespacing" section. The name of the proxy, IPAProxyRPi, comes from the name given to the main IPA interface, IPARPiInterface, in the "The Main IPA interface" section. The return value of IPAManager::createIPA shall be error-checked, to confirm that the returned pointer is not a nullptr. After this, before initializing the IPA, slots should be connected to all of the IPA's signals, as defined in the Event IPA interface: .. code-block:: C++ ipa_->statsMetadataComplete.connect(this, &RPiCameraData::statsMetadataComplete); ipa_->runIsp.connect(this, &RPiCameraData::runIsp); ipa_->embeddedComplete.connect(this, &RPiCameraData::embeddedComplete); ipa_->setIsp.connect(this, &RPiCameraData::setIsp); ipa_->setStaggered.connect(this, &RPiCameraData::setStaggered); The slot functions have a function signature based on the function definition in the Event IPA interface. All plain old data (POD) types are as-is (with their C++ versions, eg. uint32 -> uint32_t), and all structs are const references. For example, for the following entry in the Event IPA interface: .. code-block:: none statsMetadataComplete(uint32 bufferId, ControlList controls); A function with the following function signature shall be connected to the signal: .. code-block:: C++ void statsMetadataComplete(uint32_t bufferId, const ControlList &controls); After connecting the slots to the signals, the IPA should be initialized (using the main interface definition example from earlier): .. code-block:: C++ IPASettings settings{}; bool metadataSupport; int ret = ipa_->init(settings, "sensor name", &metadataSupport); At this point, any IPA functions that were defined in the Main IPA interface can be called as if they were regular member functions, for example (based on the main interface definition example from earlier): .. code-block:: C++ ipa_->start(); int ret = ipa_->configure(sensorInfo_, streamConfig, entityControls, ipaConfig, &result); ipa_->signalStatReady(RPi::BufferMask::STATS | static_cast(index)); Remember that any functions designated as asynchronous *must not* be called before start(). Notice that for both init() and configure(), the first output parameter is a direct return, since it is an int32, while the other output parameter is a pointer-based output parameter. Using the IPA interface (IPA Module) ------------------------------------ The following header is necessary to implement an IPA Module (with raspberrypi as an example): .. code-block:: C++ #include This header includes definitions of the custom data structures, and the definition of the complete IPA interface (including both the Main and the Event IPA interfaces). The name of the header file comes from the name of the mojom file, which in this case was raspberrypi.mojom. The IPA module must implement the IPA interface class that is defined in the header. In the case of our example, that is ipa::rpi::IPARPiInterface. The ipa::rpi namespace comes from the namespace that we defined in the mojo data definition file, in the "Namespacing" section. The name of the interface is the same as the name given to the Main IPA interface. The function signature rules are the same as for the slots in the pipeline handler side; PODs are passed by value, and structs are passed by const reference. For the Main IPA interface, output values are also allowed (only for synchronous calls), so there may be output parameters as well. If the first output parameter is a POD it will be returned by value, otherwise it will be returned by an output parameter pointer. The second and any other output parameters will also be returned by output parameter pointers. For example, for the following function specification in the Main IPA interface definition: .. code-block:: none configure(libcamera.IPACameraSensorInfo sensorInfo, uint32 exampleNumber, map streamConfig, map entityControls, ConfigInput ipaConfig) => (int32 ret, ConfigOutput results); We will need to implement a function with the following function signature: .. code-block:: C++ int configure(const IPACameraSensorInfo &sensorInfo, uint32_t exampleNumber, const std::map &streamConfig, const std::map &entityControls, const ipa::rpi::ConfigInput &data, ipa::rpi::ConfigOutput *response); The return value is int, because the first output parameter is int32. The rest of the output parameters (in this case, only response) become output parameter pointers. The non-POD input parameters become const references, and the POD input parameter is passed by value. At any time after start() and before stop() (though usually only in response to an IPA call), the IPA may send data to the pipeline handler by emitting signals. These signals are defined in the C++ IPA interface class (which is in the generated and included header). For example, for the following function defined in the Event IPA interface: .. code-block:: none statsMetadataComplete(uint32 bufferId, libcamera.ControlList controls); We can emit a signal like so: .. code-block:: C++ statsMetadataComplete.emit(bufferId & RPi::BufferMask::ID, libcameraMetadata_); 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 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/* SPDX-License-Identifier: ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) */
/*
 *  Video for Linux Two header file
 *
 *  Copyright (C) 1999-2012 the contributors
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  Alternatively you can redistribute this file under the terms of the
 *  BSD license as stated below:
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in
 *     the documentation and/or other materials provided with the
 *     distribution.
 *  3. The names of its contributors may not be used to endorse or promote
 *     products derived from this software without specific prior written
 *     permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 *  TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 *  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *	Header file for v4l or V4L2 drivers and applications
 * with public API.
 * All kernel-specific stuff were moved to media/v4l2-dev.h, so
 * no #if __KERNEL tests are allowed here
 *
 *	See https://linuxtv.org for more info
 *
 *	Author: Bill Dirks <bill@thedirks.org>
 *		Justin Schoeman
 *              Hans Verkuil <hverkuil@xs4all.nl>
 *		et al.
 */
#ifndef __LINUX_VIDEODEV2_H
#define __LINUX_VIDEODEV2_H

#include <sys/time.h>

#include <linux/ioctl.h>
#include <linux/types.h>
#include <linux/v4l2-common.h>
#include <linux/v4l2-controls.h>

/*
 * Common stuff for both V4L1 and V4L2
 * Moved from videodev.h
 */
#define VIDEO_MAX_FRAME               32
#define VIDEO_MAX_PLANES               8

/*
 *	M I S C E L L A N E O U S
 */

/*  Four-character-code (FOURCC) */
#define v4l2_fourcc(a, b, c, d)\
	((__u32)(a) | ((__u32)(b) << 8) | ((__u32)(c) << 16) | ((__u32)(d) << 24))
#define v4l2_fourcc_be(a, b, c, d)	(v4l2_fourcc(a, b, c, d) | (1U << 31))

/*
 *	E N U M S
 */
enum v4l2_field {
	V4L2_FIELD_ANY           = 0, /* driver can choose from none,
					 top, bottom, interlaced
					 depending on whatever it thinks
					 is approximate ... */
	V4L2_FIELD_NONE          = 1, /* this device has no fields ... */
	V4L2_FIELD_TOP           = 2, /* top field only */
	V4L2_FIELD_BOTTOM        = 3, /* bottom field only */
	V4L2_FIELD_INTERLACED    = 4, /* both fields interlaced */
	V4L2_FIELD_SEQ_TB        = 5, /* both fields sequential into one
					 buffer, top-bottom order */
	V4L2_FIELD_SEQ_BT        = 6, /* same as above + bottom-top order */
	V4L2_FIELD_ALTERNATE     = 7, /* both fields alternating into
					 separate buffers */
	V4L2_FIELD_INTERLACED_TB = 8, /* both fields interlaced, top field
					 first and the top field is
					 transmitted first */
	V4L2_FIELD_INTERLACED_BT = 9, /* both fields interlaced, top field
					 first and the bottom field is
					 transmitted first */
};
#define V4L2_FIELD_HAS_TOP(field)	\
	((field) == V4L2_FIELD_TOP	||\
	 (field) == V4L2_FIELD_INTERLACED ||\
	 (field) == V4L2_FIELD_INTERLACED_TB ||\
	 (field) == V4L2_FIELD_INTERLACED_BT ||\
	 (field) == V4L2_FIELD_SEQ_TB	||\
	 (field) == V4L2_FIELD_SEQ_BT)
#define V4L2_FIELD_HAS_BOTTOM(field)	\
	((field) == V4L2_FIELD_BOTTOM	||\
	 (field) == V4L2_FIELD_INTERLACED ||\
	 (field) == V4L2_FIELD_INTERLACED_TB ||\
	 (field) == V4L2_FIELD_INTERLACED_BT ||\
	 (field) == V4L2_FIELD_SEQ_TB	||\
	 (field) == V4L2_FIELD_SEQ_BT)
#define V4L2_FIELD_HAS_BOTH(field)	\
	((field) == V4L2_FIELD_INTERLACED ||\
	 (field) == V4L2_FIELD_INTERLACED_TB ||\
	 (field) == V4L2_FIELD_INTERLACED_BT ||\
	 (field) == V4L2_FIELD_SEQ_TB ||\
	 (field) == V4L2_FIELD_SEQ_BT)
#define V4L2_FIELD_HAS_T_OR_B(field)	\
	((field) == V4L2_FIELD_BOTTOM ||\
	 (field) == V4L2_FIELD_TOP ||\
	 (field) == V4L2_FIELD_ALTERNATE)
#define V4L2_FIELD_IS_INTERLACED(field) \
	((field) == V4L2_FIELD_INTERLACED ||\
	 (field) == V4L2_FIELD_INTERLACED_TB ||\
	 (field) == V4L2_FIELD_INTERLACED_BT)
#define V4L2_FIELD_IS_SEQUENTIAL(field) \
	((field) == V4L2_FIELD_SEQ_TB ||\
	 (field) == V4L2_FIELD_SEQ_BT)

enum v4l2_buf_type {
	V4L2_BUF_TYPE_VIDEO_CAPTURE        = 1,
	V4L2_BUF_TYPE_VIDEO_OUTPUT         = 2,
	V4L2_BUF_TYPE_VIDEO_OVERLAY        = 3,
	V4L2_BUF_TYPE_VBI_CAPTURE          = 4,
	V4L2_BUF_TYPE_VBI_OUTPUT           = 5,
	V4L2_BUF_TYPE_SLICED_VBI_CAPTURE   = 6,
	V4L2_BUF_TYPE_SLICED_VBI_OUTPUT    = 7,
	V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY = 8,
	V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE = 9,
	V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE  = 10,
	V4L2_BUF_TYPE_SDR_CAPTURE          = 11,
	V4L2_BUF_TYPE_SDR_OUTPUT           = 12,
	V4L2_BUF_TYPE_META_CAPTURE         = 13,
	V4L2_BUF_TYPE_META_OUTPUT	   = 14,
	/* Deprecated, do not use */
	V4L2_BUF_TYPE_PRIVATE              = 0x80,
};

#define V4L2_TYPE_IS_MULTIPLANAR(type)			\
	((type) == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE	\
	 || (type) == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE)

#define V4L2_TYPE_IS_OUTPUT(type)				\
	((type) == V4L2_BUF_TYPE_VIDEO_OUTPUT			\
	 || (type) == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE		\
	 || (type) == V4L2_BUF_TYPE_VIDEO_OVERLAY		\
	 || (type) == V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY	\
	 || (type) == V4L2_BUF_TYPE_VBI_OUTPUT			\
	 || (type) == V4L2_BUF_TYPE_SLICED_VBI_OUTPUT		\
	 || (type) == V4L2_BUF_TYPE_SDR_OUTPUT			\
	 || (type) == V4L2_BUF_TYPE_META_OUTPUT)

enum v4l2_tuner_type {
	V4L2_TUNER_RADIO	     = 1,
	V4L2_TUNER_ANALOG_TV	     = 2,
	V4L2_TUNER_DIGITAL_TV	     = 3,
	V4L2_TUNER_SDR               = 4,
	V4L2_TUNER_RF                = 5,
};

/* Deprecated, do not use */
#define V4L2_TUNER_ADC  V4L2_TUNER_SDR

enum v4l2_memory {
	V4L2_MEMORY_MMAP             = 1,
	V4L2_MEMORY_USERPTR          = 2,
	V4L2_MEMORY_OVERLAY          = 3,
	V4L2_MEMORY_DMABUF           = 4,
};

/* see also http://vektor.theorem.ca/graphics/ycbcr/ */
enum v4l2_colorspace {
	/*
	 * Default colorspace, i.e. let the driver figure it out.
	 * Can only be used with video capture.
	 */
	V4L2_COLORSPACE_DEFAULT       = 0,

	/* SMPTE 170M: used for broadcast NTSC/PAL SDTV */
	V4L2_COLORSPACE_SMPTE170M     = 1,

	/* Obsolete pre-1998 SMPTE 240M HDTV standard, superseded by Rec 709 */
	V4L2_COLORSPACE_SMPTE240M     = 2,

	/* Rec.709: used for HDTV */
	V4L2_COLORSPACE_REC709        = 3,

	/*
	 * Deprecated, do not use. No driver will ever return this. This was
	 * based on a misunderstanding of the bt878 datasheet.
	 */
	V4L2_COLORSPACE_BT878         = 4,

	/*
	 * NTSC 1953 colorspace. This only makes sense when dealing with
	 * really, really old NTSC recordings. Superseded by SMPTE 170M.
	 */
	V4L2_COLORSPACE_470_SYSTEM_M  = 5,

	/*
	 * EBU Tech 3213 PAL/SECAM colorspace. This only makes sense when
	 * dealing with really old PAL/SECAM recordings. Superseded by
	 * SMPTE 170M.
	 */
	V4L2_COLORSPACE_470_SYSTEM_BG = 6,

	/*
	 * Effectively shorthand for V4L2_COLORSPACE_SRGB, V4L2_YCBCR_ENC_601
	 * and V4L2_QUANTIZATION_FULL_RANGE. To be used for (Motion-)JPEG.
	 */
	V4L2_COLORSPACE_JPEG          = 7,

	/* For RGB colorspaces such as produces by most webcams. */
	V4L2_COLORSPACE_SRGB          = 8,

	/* opRGB colorspace */
	V4L2_COLORSPACE_OPRGB         = 9,

	/* BT.2020 colorspace, used for UHDTV. */
	V4L2_COLORSPACE_BT2020        = 10,

	/* Raw colorspace: for RAW unprocessed images */
	V4L2_COLORSPACE_RAW           = 11,

	/* DCI-P3 colorspace, used by cinema projectors */
	V4L2_COLORSPACE_DCI_P3        = 12,
};

/*
 * Determine how COLORSPACE_DEFAULT should map to a proper colorspace.
 * This depends on whether this is a SDTV image (use SMPTE 170M), an
 * HDTV image (use Rec. 709), or something else (use sRGB).
 */
#define V4L2_MAP_COLORSPACE_DEFAULT(is_sdtv, is_hdtv) \
	((is_sdtv) ? V4L2_COLORSPACE_SMPTE170M : \
	 ((is_hdtv) ? V4L2_COLORSPACE_REC709 : V4L2_COLORSPACE_SRGB))

enum v4l2_xfer_func {
	/*
	 * Mapping of V4L2_XFER_FUNC_DEFAULT to actual transfer functions
	 * for the various colorspaces:
	 *
	 * V4L2_COLORSPACE_SMPTE170M, V4L2_COLORSPACE_470_SYSTEM_M,
	 * V4L2_COLORSPACE_470_SYSTEM_BG, V4L2_COLORSPACE_REC709 and
	 * V4L2_COLORSPACE_BT2020: V4L2_XFER_FUNC_709
	 *
	 * V4L2_COLORSPACE_SRGB, V4L2_COLORSPACE_JPEG: V4L2_XFER_FUNC_SRGB
	 *
	 * V4L2_COLORSPACE_OPRGB: V4L2_XFER_FUNC_OPRGB
	 *
	 * V4L2_COLORSPACE_SMPTE240M: V4L2_XFER_FUNC_SMPTE240M
	 *
	 * V4L2_COLORSPACE_RAW: V4L2_XFER_FUNC_NONE
	 *
	 * V4L2_COLORSPACE_DCI_P3: V4L2_XFER_FUNC_DCI_P3
	 */
	V4L2_XFER_FUNC_DEFAULT     = 0,
	V4L2_XFER_FUNC_709         = 1,
	V4L2_XFER_FUNC_SRGB        = 2,
	V4L2_XFER_FUNC_OPRGB       = 3,
	V4L2_XFER_FUNC_SMPTE240M   = 4,
	V4L2_XFER_FUNC_NONE        = 5,
	V4L2_XFER_FUNC_DCI_P3      = 6,
	V4L2_XFER_FUNC_SMPTE2084   = 7,
};

/*
 * Determine how XFER_FUNC_DEFAULT should map to a proper transfer function.
 * This depends on the colorspace.
 */
#define V4L2_MAP_XFER_FUNC_DEFAULT(colsp) \
	((colsp) == V4L2_COLORSPACE_OPRGB ? V4L2_XFER_FUNC_OPRGB : \
	 ((colsp) == V4L2_COLORSPACE_SMPTE240M ? V4L2_XFER_FUNC_SMPTE240M : \
	  ((colsp) == V4L2_COLORSPACE_DCI_P3 ? V4L2_XFER_FUNC_DCI_P3 : \
	   ((colsp) == V4L2_COLORSPACE_RAW ? V4L2_XFER_FUNC_NONE : \
	    ((colsp) == V4L2_COLORSPACE_SRGB || (colsp) == V4L2_COLORSPACE_JPEG ? \
	     V4L2_XFER_FUNC_SRGB : V4L2_XFER_FUNC_709)))))

enum v4l2_ycbcr_encoding {
	/*
	 * Mapping of V4L2_YCBCR_ENC_DEFAULT to actual encodings for the
	 * various colorspaces:
	 *
	 * V4L2_COLORSPACE_SMPTE170M, V4L2_COLORSPACE_470_SYSTEM_M,
	 * V4L2_COLORSPACE_470_SYSTEM_BG, V4L2_COLORSPACE_SRGB,
	 * V4L2_COLORSPACE_OPRGB and V4L2_COLORSPACE_JPEG: V4L2_YCBCR_ENC_601
	 *
	 * V4L2_COLORSPACE_REC709 and V4L2_COLORSPACE_DCI_P3: V4L2_YCBCR_ENC_709
	 *
	 * V4L2_COLORSPACE_BT2020: V4L2_YCBCR_ENC_BT2020
	 *
	 * V4L2_COLORSPACE_SMPTE240M: V4L2_YCBCR_ENC_SMPTE240M
	 */
	V4L2_YCBCR_ENC_DEFAULT        = 0,

	/* ITU-R 601 -- SDTV */
	V4L2_YCBCR_ENC_601            = 1,

	/* Rec. 709 -- HDTV */
	V4L2_YCBCR_ENC_709            = 2,

	/* ITU-R 601/EN 61966-2-4 Extended Gamut -- SDTV */
	V4L2_YCBCR_ENC_XV601          = 3,

	/* Rec. 709/EN 61966-2-4 Extended Gamut -- HDTV */
	V4L2_YCBCR_ENC_XV709          = 4,

	/*
	 * sYCC (Y'CbCr encoding of sRGB), identical to ENC_601. It was added
	 * originally due to a misunderstanding of the sYCC standard. It should
	 * not be used, instead use V4L2_YCBCR_ENC_601.
	 */
	V4L2_YCBCR_ENC_SYCC           = 5,

	/* BT.2020 Non-constant Luminance Y'CbCr */
	V4L2_YCBCR_ENC_BT2020         = 6,

	/* BT.2020 Constant Luminance Y'CbcCrc */
	V4L2_YCBCR_ENC_BT2020_CONST_LUM = 7,

	/* SMPTE 240M -- Obsolete HDTV */
	V4L2_YCBCR_ENC_SMPTE240M      = 8,
};

/*
 * enum v4l2_hsv_encoding values should not collide with the ones from
 * enum v4l2_ycbcr_encoding.
 */
enum v4l2_hsv_encoding {

	/* Hue mapped to 0 - 179 */
	V4L2_HSV_ENC_180		= 128,

	/* Hue mapped to 0-255 */
	V4L2_HSV_ENC_256		= 129,
};

/*
 * Determine how YCBCR_ENC_DEFAULT should map to a proper Y'CbCr encoding.
 * This depends on the colorspace.
 */
#define V4L2_MAP_YCBCR_ENC_DEFAULT(colsp) \
	(((colsp) == V4L2_COLORSPACE_REC709 || \
	  (colsp) == V4L2_COLORSPACE_DCI_P3) ? V4L2_YCBCR_ENC_709 : \
	 ((colsp) == V4L2_COLORSPACE_BT2020 ? V4L2_YCBCR_ENC_BT2020 : \
	  ((colsp) == V4L2_COLORSPACE_SMPTE240M ? V4L2_YCBCR_ENC_SMPTE240M : \
	   V4L2_YCBCR_ENC_601)))

enum v4l2_quantization {
	/*
	 * The default for R'G'B' quantization is always full range, except
	 * for the BT2020 colorspace. For Y'CbCr the quantization is always
	 * limited range, except for COLORSPACE_JPEG: this is full range.
	 */
	V4L2_QUANTIZATION_DEFAULT     = 0,
	V4L2_QUANTIZATION_FULL_RANGE  = 1,
	V4L2_QUANTIZATION_LIM_RANGE   = 2,
};

/*
 * Determine how QUANTIZATION_DEFAULT should map to a proper quantization.
 * This depends on whether the image is RGB or not, the colorspace and the
 * Y'CbCr encoding.
 */
#define V4L2_MAP_QUANTIZATION_DEFAULT(is_rgb_or_hsv, colsp, ycbcr_enc) \
	(((is_rgb_or_hsv) && (colsp) == V4L2_COLORSPACE_BT2020) ? \
	 V4L2_QUANTIZATION_LIM_RANGE : \
	 (((is_rgb_or_hsv) || (colsp) == V4L2_COLORSPACE_JPEG) ? \
	 V4L2_QUANTIZATION_FULL_RANGE : V4L2_QUANTIZATION_LIM_RANGE))

/*
 * Deprecated names for opRGB colorspace (IEC 61966-2-5)
 *
 * WARNING: Please don't use these deprecated defines in your code, as
 * there is a chance we have to remove them in the future.
 */
#define V4L2_COLORSPACE_ADOBERGB V4L2_COLORSPACE_OPRGB
#define V4L2_XFER_FUNC_ADOBERGB  V4L2_XFER_FUNC_OPRGB

enum v4l2_priority {
	V4L2_PRIORITY_UNSET       = 0,  /* not initialized */
	V4L2_PRIORITY_BACKGROUND  = 1,
	V4L2_PRIORITY_INTERACTIVE = 2,
	V4L2_PRIORITY_RECORD      = 3,
	V4L2_PRIORITY_DEFAULT     = V4L2_PRIORITY_INTERACTIVE,
};

struct v4l2_rect {
	__s32   left;
	__s32   top;
	__u32   width;
	__u32   height;
};

struct v4l2_fract {
	__u32   numerator;
	__u32   denominator;
};

/**
  * struct v4l2_capability - Describes V4L2 device caps returned by VIDIOC_QUERYCAP
  *
  * @driver:	   name of the driver module (e.g. "bttv")
  * @card:	   name of the card (e.g. "Hauppauge WinTV")
  * @bus_info:	   name of the bus (e.g. "PCI:" + pci_name(pci_dev) )
  * @version:	   KERNEL_VERSION
  * @capabilities: capabilities of the physical device as a whole
  * @device_caps:  capabilities accessed via this particular device (node)
  * @reserved:	   reserved fields for future extensions
  */
struct v4l2_capability {
	__u8	driver[16];
	__u8	card[32];
	__u8	bus_info[32];
	__u32   version;
	__u32	capabilities;
	__u32	device_caps;
	__u32	reserved[3];
};

/* Values for 'capabilities' field */
#define V4L2_CAP_VIDEO_CAPTURE		0x00000001  /* Is a video capture device */
#define V4L2_CAP_VIDEO_OUTPUT		0x00000002  /* Is a video output device */
#define V4L2_CAP_VIDEO_OVERLAY		0x00000004  /* Can do video overlay */
#define V4L2_CAP_VBI_CAPTURE		0x00000010  /* Is a raw VBI capture device */
#define V4L2_CAP_VBI_OUTPUT		0x00000020  /* Is a raw VBI output device */
#define V4L2_CAP_SLICED_VBI_CAPTURE	0x00000040  /* Is a sliced VBI capture device */
#define V4L2_CAP_SLICED_VBI_OUTPUT	0x00000080  /* Is a sliced VBI output device */
#define V4L2_CAP_RDS_CAPTURE		0x00000100  /* RDS data capture */
#define V4L2_CAP_VIDEO_OUTPUT_OVERLAY	0x00000200  /* Can do video output overlay */
#define V4L2_CAP_HW_FREQ_SEEK		0x00000400  /* Can do hardware frequency seek  */
#define V4L2_CAP_RDS_OUTPUT		0x00000800  /* Is an RDS encoder */

/* Is a video capture device that supports multiplanar formats */
#define V4L2_CAP_VIDEO_CAPTURE_MPLANE	0x00001000
/* Is a video output device that supports multiplanar formats */
#define V4L2_CAP_VIDEO_OUTPUT_MPLANE	0x00002000
/* Is a video mem-to-mem device that supports multiplanar formats */
#define V4L2_CAP_VIDEO_M2M_MPLANE	0x00004000
/* Is a video mem-to-mem device */
#define V4L2_CAP_VIDEO_M2M		0x00008000

#define V4L2_CAP_TUNER			0x00010000  /* has a tuner */
#define V4L2_CAP_AUDIO			0x00020000  /* has audio support */
#define V4L2_CAP_RADIO			0x00040000  /* is a radio device */
#define V4L2_CAP_MODULATOR		0x00080000  /* has a modulator */

#define V4L2_CAP_SDR_CAPTURE		0x00100000  /* Is a SDR capture device */
#define V4L2_CAP_EXT_PIX_FORMAT		0x00200000  /* Supports the extended pixel format */
#define V4L2_CAP_SDR_OUTPUT		0x00400000  /* Is a SDR output device */
#define V4L2_CAP_META_CAPTURE		0x00800000  /* Is a metadata capture device */

#define V4L2_CAP_READWRITE              0x01000000  /* read/write systemcalls */
#define V4L2_CAP_ASYNCIO                0x02000000  /* async I/O */
#define V4L2_CAP_STREAMING              0x04000000  /* streaming I/O ioctls */
#define V4L2_CAP_META_OUTPUT		0x08000000  /* Is a metadata output device */

#define V4L2_CAP_TOUCH                  0x10000000  /* Is a touch device */

#define V4L2_CAP_DEVICE_CAPS            0x80000000  /* sets device capabilities field */

/*
 *	V I D E O   I M A G E   F O R M A T
 */
struct v4l2_pix_format {
	__u32			width;
	__u32			height;
	__u32			pixelformat;
	__u32			field;		/* enum v4l2_field */
	__u32			bytesperline;	/* for padding, zero if unused */
	__u32			sizeimage;
	__u32			colorspace;	/* enum v4l2_colorspace */
	__u32			priv;		/* private data, depends on pixelformat */
	__u32			flags;		/* format flags (V4L2_PIX_FMT_FLAG_*) */
	union {
		/* enum v4l2_ycbcr_encoding */
		__u32			ycbcr_enc;
		/* enum v4l2_hsv_encoding */
		__u32			hsv_enc;
	};
	__u32			quantization;	/* enum v4l2_quantization */
	__u32			xfer_func;	/* enum v4l2_xfer_func */
};

/*      Pixel format         FOURCC                          depth  Description  */

/* RGB formats */
#define V4L2_PIX_FMT_RGB332  v4l2_fourcc('R', 'G', 'B', '1') /*  8  RGB-3-3-2     */
#define V4L2_PIX_FMT_RGB444  v4l2_fourcc('R', '4', '4', '4') /* 16  xxxxrrrr ggggbbbb */
#define V4L2_PIX_FMT_ARGB444 v4l2_fourcc('A', 'R', '1', '2') /* 16  aaaarrrr ggggbbbb */
#define V4L2_PIX_FMT_XRGB444 v4l2_fourcc('X', 'R', '1', '2') /* 16  xxxxrrrr ggggbbbb */
#define V4L2_PIX_FMT_RGBA444 v4l2_fourcc('R', 'A', '1', '2') /* 16  rrrrgggg bbbbaaaa */
#define V4L2_PIX_FMT_RGBX444 v4l2_fourcc('R', 'X', '1', '2') /* 16  rrrrgggg bbbbxxxx */
#define V4L2_PIX_FMT_ABGR444 v4l2_fourcc('A', 'B', '1', '2') /* 16  aaaabbbb ggggrrrr */
#define V4L2_PIX_FMT_XBGR444 v4l2_fourcc('X', 'B', '1', '2') /* 16  xxxxbbbb ggggrrrr */

/*
 * Originally this had 'BA12' as fourcc, but this clashed with the older
 * V4L2_PIX_FMT_SGRBG12 which inexplicably used that same fourcc.
 * So use 'GA12' instead for V4L2_PIX_FMT_BGRA444.
 */
#define V4L2_PIX_FMT_BGRA444 v4l2_fourcc('G', 'A', '1', '2') /* 16  bbbbgggg rrrraaaa */
#define V4L2_PIX_FMT_BGRX444 v4l2_fourcc('B', 'X', '1', '2') /* 16  bbbbgggg rrrrxxxx */
#define V4L2_PIX_FMT_RGB555  v4l2_fourcc('R', 'G', 'B', 'O') /* 16  RGB-5-5-5     */
#define V4L2_PIX_FMT_ARGB555 v4l2_fourcc('A', 'R', '1', '5') /* 16  ARGB-1-5-5-5  */
#define V4L2_PIX_FMT_XRGB555 v4l2_fourcc('X', 'R', '1', '5') /* 16  XRGB-1-5-5-5  */
#define V4L2_PIX_FMT_RGBA555 v4l2_fourcc('R', 'A', '1', '5') /* 16  RGBA-5-5-5-1  */
#define V4L2_PIX_FMT_RGBX555 v4l2_fourcc('R', 'X', '1', '5') /* 16  RGBX-5-5-5-1  */
#define V4L2_PIX_FMT_ABGR555 v4l2_fourcc('A', 'B', '1', '5') /* 16  ABGR-1-5-5-5  */
#define V4L2_PIX_FMT_XBGR555 v4l2_fourcc('X', 'B', '1', '5') /* 16  XBGR-1-5-5-5  */
#define V4L2_PIX_FMT_BGRA555 v4l2_fourcc('B', 'A', '1', '5') /* 16  BGRA-5-5-5-1  */
#define V4L2_PIX_FMT_BGRX555 v4l2_fourcc('B', 'X', '1', '5') /* 16  BGRX-5-5-5-1  */
#define V4L2_PIX_FMT_RGB565  v4l2_fourcc('R', 'G', 'B', 'P') /* 16  RGB-5-6-5     */
#define V4L2_PIX_FMT_RGB555X v4l2_fourcc('R', 'G', 'B', 'Q') /* 16  RGB-5-5-5 BE  */
#define V4L2_PIX_FMT_ARGB555X v4l2_fourcc_be('A', 'R', '1', '5') /* 16  ARGB-5-5-5 BE */
#define V4L2_PIX_FMT_XRGB555X v4l2_fourcc_be('X', 'R', '1', '5') /* 16  XRGB-5-5-5 BE */
#define V4L2_PIX_FMT_RGB565X v4l2_fourcc('R', 'G', 'B', 'R') /* 16  RGB-5-6-5 BE  */
#define V4L2_PIX_FMT_BGR666  v4l2_fourcc('B', 'G', 'R', 'H') /* 18  BGR-6-6-6	  */
#define V4L2_PIX_FMT_BGR24   v4l2_fourcc('B', 'G', 'R', '3') /* 24  BGR-8-8-8     */
#define V4L2_PIX_FMT_RGB24   v4l2_fourcc('R', 'G', 'B', '3') /* 24  RGB-8-8-8     */
#define V4L2_PIX_FMT_BGR32   v4l2_fourcc('B', 'G', 'R', '4') /* 32  BGR-8-8-8-8   */
#define V4L2_PIX_FMT_ABGR32  v4l2_fourcc('A', 'R', '2', '4') /* 32  BGRA-8-8-8-8  */
#define V4L2_PIX_FMT_XBGR32  v4l2_fourcc('X', 'R', '2', '4') /* 32  BGRX-8-8-8-8  */
#define V4L2_PIX_FMT_BGRA32  v4l2_fourcc('R', 'A', '2', '4') /* 32  ABGR-8-8-8-8  */
#define V4L2_PIX_FMT_BGRX32  v4l2_fourcc('R', 'X', '2', '4') /* 32  XBGR-8-8-8-8  */
#define V4L2_PIX_FMT_RGB32   v4l2_fourcc('R', 'G', 'B', '4') /* 32  RGB-8-8-8-8   */
#define V4L2_PIX_FMT_RGBA32  v4l2_fourcc('A', 'B', '2', '4') /* 32  RGBA-8-8-8-8  */
#define V4L2_PIX_FMT_RGBX32  v4l2_fourcc('X', 'B', '2', '4') /* 32  RGBX-8-8-8-8  */
#define V4L2_PIX_FMT_ARGB32  v4l2_fourcc('B', 'A', '2', '4') /* 32  ARGB-8-8-8-8  */
#define V4L2_PIX_FMT_XRGB32  v4l2_fourcc('B', 'X', '2', '4') /* 32  XRGB-8-8-8-8  */

/* Grey formats */
#define V4L2_PIX_FMT_GREY    v4l2_fourcc('G', 'R', 'E', 'Y') /*  8  Greyscale     */
#define V4L2_PIX_FMT_Y4      v4l2_fourcc('Y', '0', '4', ' ') /*  4  Greyscale     */
#define V4L2_PIX_FMT_Y6      v4l2_fourcc('Y', '0', '6', ' ') /*  6  Greyscale     */
#define V4L2_PIX_FMT_Y10     v4l2_fourcc('Y', '1', '0', ' ') /* 10  Greyscale     */
#define V4L2_PIX_FMT_Y12     v4l2_fourcc('Y', '1', '2', ' ') /* 12  Greyscale     */
#define V4L2_PIX_FMT_Y16     v4l2_fourcc('Y', '1', '6', ' ') /* 16  Greyscale     */
#define V4L2_PIX_FMT_Y16_BE  v4l2_fourcc_be('Y', '1', '6', ' ') /* 16  Greyscale BE  */

/* Grey bit-packed formats */
#define V4L2_PIX_FMT_Y10BPACK    v4l2_fourcc('Y', '1', '0', 'B') /* 10  Greyscale bit-packed */
#define V4L2_PIX_FMT_Y10P    v4l2_fourcc('Y', '1', '0', 'P') /* 10  Greyscale, MIPI RAW10 packed */

/* Palette formats */
#define V4L2_PIX_FMT_PAL8    v4l2_fourcc('P', 'A', 'L', '8') /*  8  8-bit palette */

/* Chrominance formats */
#define V4L2_PIX_FMT_UV8     v4l2_fourcc('U', 'V', '8', ' ') /*  8  UV 4:4 */

/* Luminance+Chrominance formats */
#define V4L2_PIX_FMT_YUYV    v4l2_fourcc('Y', 'U', 'Y', 'V') /* 16  YUV 4:2:2     */
#define V4L2_PIX_FMT_YYUV    v4l2_fourcc('Y', 'Y', 'U', 'V') /* 16  YUV 4:2:2     */
#define V4L2_PIX_FMT_YVYU    v4l2_fourcc('Y', 'V', 'Y', 'U') /* 16 YVU 4:2:2 */
#define V4L2_PIX_FMT_UYVY    v4l2_fourcc('U', 'Y', 'V', 'Y') /* 16  YUV 4:2:2     */
#define V4L2_PIX_FMT_VYUY    v4l2_fourcc('V', 'Y', 'U', 'Y') /* 16  YUV 4:2:2     */
#define V4L2_PIX_FMT_Y41P    v4l2_fourcc('Y', '4', '1', 'P') /* 12  YUV 4:1:1     */
#define V4L2_PIX_FMT_YUV444  v4l2_fourcc('Y', '4', '4', '4') /* 16  xxxxyyyy uuuuvvvv */
#define V4L2_PIX_FMT_YUV555  v4l2_fourcc('Y', 'U', 'V', 'O') /* 16  YUV-5-5-5     */
#define V4L2_PIX_FMT_YUV565  v4l2_fourcc('Y', 'U', 'V', 'P') /* 16  YUV-5-6-5     */
#define V4L2_PIX_FMT_YUV32   v4l2_fourcc('Y', 'U', 'V', '4') /* 32  YUV-8-8-8-8   */
#define V4L2_PIX_FMT_AYUV32  v4l2_fourcc('A', 'Y', 'U', 'V') /* 32  AYUV-8-8-8-8  */
#define V4L2_PIX_FMT_XYUV32  v4l2_fourcc('X', 'Y', 'U', 'V') /* 32  XYUV-8-8-8-8  */
#define V4L2_PIX_FMT_VUYA32  v4l2_fourcc('V', 'U', 'Y', 'A') /* 32  VUYA-8-8-8-8  */
#define V4L2_PIX_FMT_VUYX32  v4l2_fourcc('V', 'U', 'Y', 'X') /* 32  VUYX-8-8-8-8  */
#define V4L2_PIX_FMT_HI240   v4l2_fourcc('H', 'I', '2', '4') /*  8  8-bit color   */
#define V4L2_PIX_FMT_HM12    v4l2_fourcc('H', 'M', '1', '2') /*  8  YUV 4:2:0 16x16 macroblocks */
#define V4L2_PIX_FMT_M420    v4l2_fourcc('M', '4', '2', '0') /* 12  YUV 4:2:0 2 lines y, 1 line uv interleaved */

/* two planes -- one Y, one Cr + Cb interleaved  */
#define V4L2_PIX_FMT_NV12    v4l2_fourcc('N', 'V', '1', '2') /* 12  Y/CbCr 4:2:0  */
#define V4L2_PIX_FMT_NV21    v4l2_fourcc('N', 'V', '2', '1') /* 12  Y/CrCb 4:2:0  */
#define V4L2_PIX_FMT_NV16    v4l2_fourcc('N', 'V', '1', '6') /* 16  Y/CbCr 4:2:2  */
#define V4L2_PIX_FMT_NV61    v4l2_fourcc('N', 'V', '6', '1') /* 16  Y/CrCb 4:2:2  */
#define V4L2_PIX_FMT_NV24    v4l2_fourcc('N', 'V', '2', '4') /* 24  Y/CbCr 4:4:4  */
#define V4L2_PIX_FMT_NV42    v4l2_fourcc('N', 'V', '4', '2') /* 24  Y/CrCb 4:4:4  */

/* two non contiguous planes - one Y, one Cr + Cb interleaved  */
#define V4L2_PIX_FMT_NV12M   v4l2_fourcc('N', 'M', '1', '2') /* 12  Y/CbCr 4:2:0  */
#define V4L2_PIX_FMT_NV21M   v4l2_fourcc('N', 'M', '2', '1') /* 21  Y/CrCb 4:2:0  */
#define V4L2_PIX_FMT_NV16M   v4l2_fourcc('N', 'M', '1', '6') /* 16  Y/CbCr 4:2:2  */
#define V4L2_PIX_FMT_NV61M   v4l2_fourcc('N', 'M', '6', '1') /* 16  Y/CrCb 4:2:2  */
#define V4L2_PIX_FMT_NV12MT  v4l2_fourcc('T', 'M', '1', '2') /* 12  Y/CbCr 4:2:0 64x32 macroblocks */
#define V4L2_PIX_FMT_NV12MT_16X16 v4l2_fourcc('V', 'M', '1', '2') /* 12  Y/CbCr 4:2:0 16x16 macroblocks */

/* three planes - Y Cb, Cr */
#define V4L2_PIX_FMT_YUV410  v4l2_fourcc('Y', 'U', 'V', '9') /*  9  YUV 4:1:0     */
#define V4L2_PIX_FMT_YVU410  v4l2_fourcc('Y', 'V', 'U', '9') /*  9  YVU 4:1:0     */
#define V4L2_PIX_FMT_YUV411P v4l2_fourcc('4', '1', '1', 'P') /* 12  YVU411 planar */
#define V4L2_PIX_FMT_YUV420  v4l2_fourcc('Y', 'U', '1', '2') /* 12  YUV 4:2:0     */
#define V4L2_PIX_FMT_YVU420  v4l2_fourcc('Y', 'V', '1', '2') /* 12  YVU 4:2:0     */
#define V4L2_PIX_FMT_YUV422P v4l2_fourcc('4', '2', '2', 'P') /* 16  YVU422 planar */

/* three non contiguous planes - Y, Cb, Cr */
#define V4L2_PIX_FMT_YUV420M v4l2_fourcc('Y', 'M', '1', '2') /* 12  YUV420 planar */
#define V4L2_PIX_FMT_YVU420M v4l2_fourcc('Y', 'M', '2', '1') /* 12  YVU420 planar */
#define V4L2_PIX_FMT_YUV422M v4l2_fourcc('Y', 'M', '1', '6') /* 16  YUV422 planar */
#define V4L2_PIX_FMT_YVU422M v4l2_fourcc('Y', 'M', '6', '1') /* 16  YVU422 planar */
#define V4L2_PIX_FMT_YUV444M v4l2_fourcc('Y', 'M', '2', '4') /* 24  YUV444 planar */
#define V4L2_PIX_FMT_YVU444M v4l2_fourcc('Y', 'M', '4', '2') /* 24  YVU444 planar */

/* Bayer formats - see http://www.siliconimaging.com/RGB%20Bayer.htm */
#define V4L2_PIX_FMT_SBGGR8  v4l2_fourcc('B', 'A', '8', '1') /*  8  BGBG.. GRGR.. */
#define V4L2_PIX_FMT_SGBRG8  v4l2_fourcc('G', 'B', 'R', 'G') /*  8  GBGB.. RGRG.. */
#define V4L2_PIX_FMT_SGRBG8  v4l2_fourcc('G', 'R', 'B', 'G') /*  8  GRGR.. BGBG.. */
#define V4L2_PIX_FMT_SRGGB8  v4l2_fourcc('R', 'G', 'G', 'B') /*  8  RGRG.. GBGB.. */
#define V4L2_PIX_FMT_SBGGR10 v4l2_fourcc('B', 'G', '1', '0') /* 10  BGBG.. GRGR.. */
#define V4L2_PIX_FMT_SGBRG10 v4l2_fourcc('G', 'B', '1', '0') /* 10  GBGB.. RGRG.. */
#define V4L2_PIX_FMT_SGRBG10 v4l2_fourcc('B', 'A', '1', '0') /* 10  GRGR.. BGBG.. */
#define V4L2_PIX_FMT_SRGGB10 v4l2_fourcc('R', 'G', '1', '0') /* 10  RGRG.. GBGB.. */
	/* 10bit raw bayer packed, 5 bytes for every 4 pixels */
#define V4L2_PIX_FMT_SBGGR10P v4l2_fourcc('p', 'B', 'A', 'A')
#define V4L2_PIX_FMT_SGBRG10P v4l2_fourcc('p', 'G', 'A', 'A')
#define V4L2_PIX_FMT_SGRBG10P v4l2_fourcc('p', 'g', 'A', 'A')