[libcamera-devel] [PATCH v2 00/27] libcamera: Handle fallout of FrameBuffer offset support

David Plowman david.plowman at raspberrypi.com
Mon Sep 6 13:22:25 CEST 2021


Hi Laurent, everyone

Thanks for all the efforts to get this working! I had just a little
question or two...

1. Is it easy to tell if a FrameBuffer is actually single plane or
multi plane? If not, could we add a public API function that would
tell us?

2. Is it easy to get the full size of the buffer for the single plane
case (rather than having to add all the bits up)? And again, if the
answer is no, could we add such a thing?

I'm thinking of trying to make life easy for applications that might
want to pass these buffers to codecs where the driver might only
support single planes. Not thinking of any platform in particular...
:)

Thanks!
David

On Mon, 6 Sept 2021 at 03:01, Laurent Pinchart
<laurent.pinchart at ideasonboard.com> wrote:
>
> Hello everybody,
>
> This patch series started as an investigation of a qcam failure with
> IPU3 after the merge of the FrameBuffer offset support. While a hack in
> qcam would be possible, I decided to instead address the core issue and
> fix it in V4L2VideoDevice.
>
> Compared to v1, the series now includes fixes for cam and qcam in
> addition to the changes needed in the libcamera core. They have been
> tested with the Raspberry Pi, IPU3, VIMC and UVC pipeline handlers.
>
> The GStreamer element seems to work fine without any change required.
> The V4L2 compatibility layer is still broken, and I haven't tested the
> Android HAL yet (any volunteer ?).
>
> The most important change is in patches 13/27 and 14/27, which translate
> between V4L2 buffers and libcamera FrameBuffer to handle the case where
> a multi-planar frame buffer is used with the V4L2 single-planar API.
> It's working more or less by chance at the moment (except in qcam where
> it's broken, and possibly in other places I haven't tested). Patches
> 01/27 to 12/27 are cleanups and additions to prepare for the work in
> V4L2VideoDevice, and patch 15/27 is a small cleanup on top. Patches
> 16/27 and 17/27 then improve the FrameBuffer class API as a cleanup.
>
> Patches 18/27 to 27/27 fix the cam and qcam applications, as well as an
> issue in the Android HAL. Worth being noted is patch 19/27 that
> introduces an Image class shared by cam and qcam. The class duplicates
> the MappedFrameBuffer implementation private to libcamera. I've tried to
> rework MappedFrameBuffer into something I would be happy to see in the
> public API, but failed to do so in a reasonable amount of time, and I
> didn't want to delay this important regression fix.
>
> This series doesn't break any unit test, as vimc doesn't support NV12.
> Addition of NV12 support to the vimc kernel driver would be very nice,
> in order to test multi-planar support in our unit tests. Volunteers are
> welcome ;-)
>
> Laurent Pinchart (27):
>   libcamera: base: utils: Use size_t for index in utils::enumerate()
>   libcamera: file_descriptor: Add a function to retrieve the inode
>   libcamera: v4l2_videodevice: Drop toV4L2PixelFormat()
>   libcamera: Use V4L2PixelFormat::fromPixelFormat()
>   libcamera: formats: Move plane info structure to PixelFormatInfo
>   libcamera: formats: Add planeSize() helpers to PixelFormatInfo
>   libcamera: formats: Support V4L2 non-contiguous formats
>   libcamera: framebuffer: Move planes check to constructor
>   libcamera: framebuffer: Add a function to check if planes are
>     contiguous
>   libcamera: v4l2_videodevice: Cache PixelFormatInfo
>   libcamera: v4l2_videodevice: Document plane handling in createBuffer()
>   libcamera: v4l2_videodevice: Take stride into account to compute
>     offsets
>   libcamera: v4l2_videodevice: Coalesce planes when queuing buffer
>   libcamera: v4l2_videodevice: Split planes when dequeuing buffer
>   libcamera: v4l2_videodevice: Use utils::enumerate()
>   libcamera: framebuffer: Allocate metadata planes at construction time
>   libcamera: framebuffer: Prevent modifying the number of metadata
>     planes
>   android: camera_device: Don't assume all planes use the same fd
>   cam: Add Image class
>   cam: file_sink: Use Image class to access pixel data
>   cam: drm: Support per-plane stride values
>   cam: drm: Set per-plane offsets when creating DRM frame buffer
>   cam: drm: Avoid importing the same dmabuf multiple times
>   qcam: Print bytesused for all planes
>   qcam: Use Image class to access pixel data
>   qcam: viewfinder_gl: Support multi-planar buffers
>   qcam: viewfinder_qt: Support multi-planar buffers
>
>  include/libcamera/base/utils.h                |   4 +-
>  include/libcamera/file_descriptor.h           |   3 +
>  include/libcamera/framebuffer.h               |  19 +-
>  include/libcamera/internal/formats.h          |  22 +-
>  include/libcamera/internal/framebuffer.h      |   2 +
>  include/libcamera/internal/v4l2_pixelformat.h |   2 +-
>  include/libcamera/internal/v4l2_videodevice.h |   3 +-
>  src/android/camera_device.cpp                 |  25 +-
>  src/android/mm/generic_camera_buffer.cpp      |  11 +-
>  src/android/yuv/post_processor_yuv.cpp        |  10 +-
>  src/cam/camera_session.cpp                    |   4 +-
>  src/cam/drm.cpp                               |  38 +-
>  src/cam/drm.h                                 |   7 +-
>  src/cam/file_sink.cpp                         |  44 +--
>  src/cam/file_sink.h                           |   6 +-
>  src/cam/image.cpp                             | 107 +++++
>  src/cam/image.h                               |  52 +++
>  src/cam/kms_sink.cpp                          |  28 +-
>  src/cam/meson.build                           |   1 +
>  src/libcamera/file_descriptor.cpp             |  26 ++
>  src/libcamera/formats.cpp                     | 373 ++++++++++++++----
>  src/libcamera/framebuffer.cpp                 |  57 ++-
>  src/libcamera/pipeline/ipu3/cio2.cpp          |   4 +-
>  src/libcamera/pipeline/ipu3/imgu.cpp          |   2 +-
>  .../pipeline/raspberrypi/raspberrypi.cpp      |   8 +-
>  src/libcamera/pipeline/rkisp1/rkisp1_path.cpp |   6 +-
>  src/libcamera/pipeline/simple/converter.cpp   |   8 +-
>  src/libcamera/pipeline/simple/simple.cpp      |   4 +-
>  src/libcamera/pipeline/uvcvideo/uvcvideo.cpp  |   6 +-
>  src/libcamera/pipeline/vimc/vimc.cpp          |   8 +-
>  src/libcamera/v4l2_pixelformat.cpp            |  11 +-
>  src/libcamera/v4l2_videodevice.cpp            | 196 ++++++---
>  src/qcam/format_converter.cpp                 |  18 +-
>  src/qcam/format_converter.h                   |   9 +-
>  src/qcam/main_window.cpp                      |  38 +-
>  src/qcam/main_window.h                        |   4 +-
>  src/qcam/meson.build                          |   1 +
>  src/qcam/viewfinder.h                         |   6 +-
>  src/qcam/viewfinder_gl.cpp                    |  45 +--
>  src/qcam/viewfinder_gl.h                      |   4 +-
>  src/qcam/viewfinder_qt.cpp                    |  20 +-
>  src/qcam/viewfinder_qt.h                      |   2 +-
>  src/v4l2/v4l2_camera_proxy.cpp                |  11 +-
>  test/libtest/buffer_source.cpp                |   3 +-
>  test/utils.cpp                                |  10 +-
>  45 files changed, 911 insertions(+), 357 deletions(-)
>  create mode 100644 src/cam/image.cpp
>  create mode 100644 src/cam/image.h
>
> --
> Regards,
>
> Laurent Pinchart
>


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