When CPU ISP is asked to apply the CCM matrix
[0 1 0]
[0 0 0]
[0 0 0]
for a format that requires swapping red and blue channels, the resulting
image has a wrong colour. The CCM matrix above should take green from
pixels and make it red. Instead, the image is blue.
The problem is that the lookup tables setup in CPU debayering swaps red
and blue in the lookup tables for red and blue, but not for green. The
colours must be swapped also in the lookup table for green, which this
patch adds.
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
The window coordinates passed to SwStatsCpu::setWindow are confusing.
Let's clarify what the coordinates should be.
A source of confusion is that the specified window is relative to the
processed area. Debayering adjusts line pointers for its processed area
and this is what's also passed to stats processing. The window passed
to SwStatsCpu::setWindow should either specify the size of the whole
processed (not image) area, or its cropping in case the stats shouldn't
be gathered over the whole processed area. This patch should clarify
this in the code.
Reviewed-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Reviewed-by: Hans de Goede <hansg@kernel.org>
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Reviewed-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com>
Tested-by: Hans de Goede <hansg@kernel.org>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Run sw-statistics once every 4th frame, instead of every frame. There are
2 reasons for this:
1. There really is no need to have statistics for every frame and only
doing this every 4th frame helps save some CPU time.
2. The generic nature of the simple pipeline-handler, so no information
about possible CSI receiver frame-delays. In combination with the software
ISP often being used with sensors without sensor info in the sensor-helper
code, so no reliable control-delay information means that the software ISP
is prone to AGC oscillation. Skipping statistics gathering also means
skipping running the AGC algorithm slowing it down, avoiding this
oscillation.
Note ideally the AGC oscillation problem would be fixed by adding sensor
metadata support all through the stack so that the exact gain and exposure
used for a specific frame are reliably provided by the sensor metadata.
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Tested-by: Milan Zamazal <mzamazal@redhat.com>
Tested-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Hans de Goede <hansg@kernel.org>
Reviewed-by: Milan Zamazal <mzamazal@redhat.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Software ISP performs performance measurement on certain part of initial
frames. Let's make this range configurable.
For this purpose, this patch introduces new configuration options
software_isp.measure.skip and software_isp.measure.number. Setting the
latter one to 0 disables the measurement.
Instead of the last frame, the class member and its configuration
specify the number of frames to measure. This is easier to use for
users and doesn't require to adjust two configuration parameters when
the number of the initially skipped frames is changed.
The patch also changes the names of the class members to make them more
accurate.
Completes software ISP TODO #7.
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
On some platforms, working directly on the input buffer is very slow due
to disabled caching. This is why we copy the input buffer into standard
(cached) memory. This is an unnecessary overhead on platforms with
cached buffers.
Let's make input buffer copying configurable. The default is still
copying, as its overhead is much lower than contingent operations on
non-cached memory. Ideally, we should improve this in future to set the
default to non-copying if we can be sure under observable circumstances
that we are working with cached buffers.
Completes software ISP TODO #6.
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
This patch applies color correction matrix (CCM) in debayering if the
CCM is specified. Not using CCM must still be supported for performance
reasons.
The CCM is applied as follows:
[r1 g1 b1] [r]
[r2 g2 b2] * [g]
[r3 g3 b3] [b]
The CCM matrix (the left side of the multiplication) is constant during
single frame processing, while the input pixel (the right side) changes.
Because each of the color channels is only 8-bit in software ISP, we can
make 9 lookup tables with 256 input values for multiplications of each
of the r_i, g_i, b_i values. This way we don't have to multiply each
pixel, we can use table lookups and additions instead. Gamma (which is
non-linear and thus cannot be a part of the 9 lookup tables values) is
applied on the final values rounded to integers using another lookup
table.
Because the changing part is the pixel value with three color elements,
only three dynamic table lookups are needed. We use three lookup tables
to represent the multiplied matrix values, each of the tables
corresponding to the given matrix column and pixel color.
We use int16_t to store the precomputed multiplications. This seems to
be noticeably (>10%) faster than `float' for the price of slightly less
accuracy and it covers the range of values that sane CCMs produce. The
selection and structure of data is performance critical, for example
using bytes would add significant (>10%) speedup but would be too short
to cover the value range.
The color lookup tables can be represented either as unions,
accommodating tables for both the CCM and non-CCM cases, or as separate
tables for each of the cases, leaving the tables for the other case
unused. The latter is selected as a matter of preference.
The tables are copied (as before), which is not elegant but also not a
big problem. There are patches posted that use shared buffers for
parameters passing in software ISP (see software ISP TODO #5) and they
can be adjusted for the new parameter format.
Color gains from white balance are supposed not to be a part of the
specified CCM. They are applied on it using matrix multiplication,
which is simple and in correspondence with future additions in the form
of matrix multiplication, like saturation adjustment.
With this patch, the reported per-frame slowdown when applying CCM is
about 45% on Debix Model A and about 75% on TI AM69 SK.
Using std::clamp in debayering adds some performance penalty (a few
percent). The clamping is necessary to eliminate out of range values
possibly produced by the CCM. If it could be avoided by adjusting the
precomputed tables some way then performance could be improved a bit.
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Applying color correction matrix (CCM) in software ISP is optional due
to performance reasons. CCM is applied if and only if `Ccm' algorithm
is present in the tuning file.
Software ISP debayering is a performance critical piece of code and we
do not want to use dynamic conditionals there. Therefore we pass
information about CCM application to debayering configuration and let it
select the right versions of debayering functions using templates. This
is a trick similar to the previously used one for adding or not adding
an alpha channel to the output.
Debayering gets this information but it ignores it in this patch.
Actual processing with CCM is added in the followup patch.
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Assignments of the debayering methods to be used is a repetitive pattern
that can be (arguably) better expressed by using a macro. This removes
some duplication and also makes easier to introduce more complex
assignment patterns. This will be useful once color correction matrix
support is added.
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
A previous preparation patch implemented passing frame ids to stats
processing but without actual meaningful frame id value passed there.
This patch extends that by actually providing the frame id and passing
it through to the stats processor.
The frame id is taken from the request sequence number, the same as in
hardware pipelines.
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
This patch adds frame and bufferId arguments to stats related calls.
Although the parameters are currently unused, because frame ids are not
tracked and used and the stats buffer is passed around directly rather
than being referred by its id, they bring the internal APIs closer to
their counterparts in hardware pipelines.
It serves as a preparation for followup patches that will introduce:
- Frame number tracking in order to switch to DelayedControls
(software ISP TODO #11 + #12).
- A ring buffer for stats in order to improve passing the stats
(software ISP TODO #2).
Frame and buffer ids are unrelated for the given purposes but since they
are passed together at the same places, the change is implemented as a
single patch rather than two, basically the same, patches.
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Using `DMA_BUF_IOCTL_SYNC` is required for DMABUFs in order to ensure
correct output. Not doing so currently results in occasional tearing
and/or backlashes in GL/VK clients that use the buffers directly for
rendering.
An alternative approach to have the sync code in `MappedFrameBuffer` was
considered but rejected for now, in order to allow clients more
flexibility.
While the new helper is added to an annoymous namespace, add
timeDiff to the same namespace and remove the static definition as a
drive by.
Signed-off-by: Robert Mader <robert.mader@collabora.com>
Tested-by: Milan Zamazal <mzamazal@redhat.com> # Debix
Tested-by: Hans de Goede <hdegoede@redhat.com> # IPU6 + ov2740
Tested-by: Kieran Bingham <kieran.bingham@ideasonboard.com> # Lenovo X13s + OV5675
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
libcamera is implemented in C++, use std::vector<> to manage the
dynamically allocated line buffers instead of malloc() and free(). This
simplifies the code and improves memory safety by ensuring no allocation
will be leaked.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Milan Zamazal <mzamazal@redhat.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
In order to be more compatible with modern hardware and APIs. This
notably allows GL implementations to directly import the buffers more
often and seems to be required for Wayland.
Further more, as we already enforce a 8 byte stride, these formats work
better for clients that don't support padding - such as libwebrtc at the
time of writing.
Tested devices:
- Librem5
- PinePhone
- Thinkpad X13s
Signed-off-by: Robert Mader <robert.mader@collabora.com>
Tested-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Milan Zamazal <mzamazal@redhat.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Constructing the color mapping tables is related to stats rather than
debayering, where they are applied. Let's move the corresponding code
to stats processing.
The same applies to the auxiliary gamma table. As the gamma value is
currently fixed and used in a single place, with the temporary exception
mentioned below, there is no need to share it anywhere anymore.
It's necessary to initialize SoftwareIsp::debayerParams_ to default
values. These initial values are used for the first two frames, before
they are changed based on determined stats. To avoid sharing the gamma
value constant in artificial ways, we use 0.5 directly in the
initialization. This all is not a particularly elegant thing to do,
such a code belongs conceptually to the similar code in stats
processing, but doing better is left for larger refactoring.
This is a preliminary step towards building this functionality on top of
libipa/algorithm.h, which should follow.
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Reviewed-by: Andrei Konovalov <andrey.konovalov.ynk@gmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Source files in libcamera start by a comment block header, which
includes the file name and a one-line description of the file contents.
While the latter is useful to get a quick overview of the file contents
at a glance, the former is mostly a source of inconvenience. The name in
the comments can easily get out of sync with the file name when files
are renamed, and copy & paste during development have often lead to
incorrect names being used to start with.
Readers of the source code are expected to know which file they're
looking it. Drop the file name from the header comment block.
The change was generated with the following script:
----------------------------------------
dirs="include/libcamera src test utils"
declare -rA patterns=(
['c']=' \* '
['cpp']=' \* '
['h']=' \* '
['py']='# '
['sh']='# '
)
for ext in ${!patterns[@]} ; do
files=$(for dir in $dirs ; do find $dir -name "*.${ext}" ; done)
pattern=${patterns[${ext}]}
for file in $files ; do
name=$(basename ${file})
sed -i "s/^\(${pattern}\)${name} - /\1/" "$file"
done
done
----------------------------------------
This misses several files that are out of sync with the comment block
header. Those will be addressed separately and manually.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>
Black may not be represented as 0 pixel value for given hardware, it may
be higher. If this is not compensated then various problems may occur
such as low contrast or suboptimal exposure.
The black pixel value can be either retrieved from a tuning file for the
given hardware, or automatically on the fly. The former is the right
and correct method, while the latter can be used when a tuning file is
not available for the given hardware. Since there is currently no
support for tuning files in software ISP, the automatic, hardware
independent way, is always used. Support for tuning files should be
added in future but it will require more work than this patch.
The patch looks at the image histogram and assumes that black starts
when pixel values start occurring on the left. A certain amount of the
darkest pixels is ignored; it doesn't matter whether they represent
various kinds of noise or are real, they are better to omit in any case
to make the image looking better. It also doesn't matter whether the
darkest pixels occur around the supposed black level or are spread
between 0 and the black level, the difference is not important.
An arbitrary threshold of 2% darkest pixels is applied; there is no
magic about that value.
The patch assumes that the black values for different colors are the
same and doesn't attempt any other non-primitive enhancements. It
cannot completely replace tuning files and simplicity, while providing
visible benefit, is its goal. Anything more sophisticated is left for
future patches.
A possible cheap enhancement, if needed, could be setting exposure +
gain to minimum values temporarily, before setting the black level. In
theory, the black level should be fixed but it may not be reached in all
images. For this reason, the patch updates black level only if the
observed value is lower than the current one; it should be never
increased.
The purpose of the patch is to compensate for hardware properties.
General image contrast enhancements are out of scope of this patch.
Stats are still gathered as an uncorrected histogram, to avoid any
confusion and to represent the raw image data. Exposure must be
determined after the black level correction -- it has no influence on
the sub-black area and must be correct after applying the black level
correction. The granularity of the histogram is increased from 16 to 64
to provide a better precision (there is no theory behind either of those
numbers).
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Milan Zamazal <mzamazal@redhat.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
