[RFC 4/4] libcamera: swstats_cpu: Add processFrame() method

[Hans de Goede]

Hi,

On 10-Oct-24 1:15 AM, Kieran Bingham wrote:
> Quoting Hans de Goede (2024-10-09 21:01:10)
>> Add a method to the SwstatsCpu class to process a whole Framebuffer in
>> one go, rather then line by line. This is useful for gathering stats
>> when debayering is not necessary or is not done on the CPU.
> 
> I can't see how this is used yet. Is it just something that you would be
> able to directly set up and call on a frame explicitly if desired?

Yes that is the idea. It could be e.g. used to do a raw-bayer pipeline
while still having 3A in place.

> I expect that's possible as it's RFC ... So I think I'll leave this one
> to other soft-isp devs... But I can understand that it could be useful
> for future development.

Regards,

Hans




>> ---
>>  src/libcamera/software_isp/swstats_cpu.cpp | 72 ++++++++++++++++++++++
>>  src/libcamera/software_isp/swstats_cpu.h   | 10 +++
>>  2 files changed, 82 insertions(+)
>>
>> diff --git a/src/libcamera/software_isp/swstats_cpu.cpp b/src/libcamera/software_isp/swstats_cpu.cpp
>> index 5e4246a9..117147c2 100644
>> --- a/src/libcamera/software_isp/swstats_cpu.cpp
>> +++ b/src/libcamera/software_isp/swstats_cpu.cpp
>> @@ -16,6 +16,7 @@
>>  #include <libcamera/stream.h>
>>  
>>  #include "libcamera/internal/bayer_format.h"
>> +#include "libcamera/internal/mapped_framebuffer.h"
>>  
>>  namespace libcamera {
>>  
>> @@ -363,8 +364,11 @@ int SwStatsCpu::configure(const StreamConfiguration &inputCfg)
>>         BayerFormat bayerFormat =
>>                 BayerFormat::fromPixelFormat(inputCfg.pixelFormat);
>>  
>> +       stride_ = inputCfg.stride;
>> +
>>         if (bayerFormat.packing == BayerFormat::Packing::None &&
>>             setupStandardBayerOrder(bayerFormat.order) == 0) {
>> +               bpp_ = (bayerFormat.bitDepth + 7) & ~7;
>>                 switch (bayerFormat.bitDepth) {
>>                 case 8:
>>                         stats0_ = &SwStatsCpu::statsBGGR8Line0;
>> @@ -385,6 +389,7 @@ int SwStatsCpu::configure(const StreamConfiguration &inputCfg)
>>                 /* Skip every 3th and 4th line, sample every other 2x2 block */
>>                 ySkipMask_ = 0x02;
>>                 xShift_ = 0;
>> +               bpp_ = 10;
>>  
>>                 switch (bayerFormat.order) {
>>                 case BayerFormat::BGGR:
>> @@ -425,4 +430,71 @@ void SwStatsCpu::setWindow(const Rectangle &window)
>>         window_.height &= ~(patternSize_.height - 1);
>>  }
>>  
>> +void SwStatsCpu::processFrame2(const uint8_t *src)
>> +{
>> +       unsigned int yEnd = window_.y + window_.height;
>> +       const uint8_t *linePointers[3];
>> +
>> +       /* Adjust src to top left corner of the window */
>> +       src += window_.y * stride_ + window_.x * bpp_ / 8;
>> +
>> +       for (unsigned int y = window_.y; y < yEnd; y += 2) {
>> +               if (y & ySkipMask_) {
>> +                       src += stride_ * 2;
>> +                       continue;
>> +               }
>> +
>> +               /* linePointers[0] is not used by any stats0_ functions */
>> +               linePointers[1] = src;
>> +               linePointers[2] = src + stride_;
>> +               (this->*stats0_)(linePointers);
>> +               src += stride_ * 2;
>> +       }
>> +}
>> +
>> +void SwStatsCpu::processFrame4(const uint8_t *src)
>> +{
>> +       const unsigned int yEnd = window_.y + window_.height;
>> +       const uint8_t *linePointers[4];
>> +
>> +       /* Adjust src to top left corner of the window */
>> +       src += window_.y * stride_ + window_.x * bpp_ / 8;
>> +
>> +       for (unsigned int y = window_.y; y < yEnd; y += 4) {
>> +               if (y & ySkipMask_) {
>> +                       src += stride_ * 4;
>> +                       continue;
>> +               }
>> +
>> +               /* linePointers[0] and [1] are not used by 4 line pattern stats0_ functions */
>> +               linePointers[2] = src;
>> +               linePointers[3] = src + stride_;
>> +               (this->*stats0_)(linePointers);
>> +               src += stride_ * 2;
>> +
>> +               linePointers[2] = src;
>> +               linePointers[3] = src + stride_;
>> +               (this->*stats2_)(linePointers);
>> +               src += stride_ * 2;
>> +       }
>> +}
>> +
>> +void SwStatsCpu::processFrame(FrameBuffer *input)
>> +{
>> +       bench_.startFrame();
>> +
>> +       MappedFrameBuffer in(input, MappedFrameBuffer::MapFlag::Read);
>> +       if (!in.isValid()) {
>> +               LOG(SwStatsCpu, Error) << "mmap-ing buffer(s) failed";
>> +               return;
>> +       }
>> +
>> +       if (patternSize_.height == 2)
>> +               processFrame2(in.planes()[0].data());
>> +       else
>> +               processFrame4(in.planes()[0].data());
>> +
>> +       bench_.finishFrame();
>> +}
>> +
>>  } /* namespace libcamera */
>> diff --git a/src/libcamera/software_isp/swstats_cpu.h b/src/libcamera/software_isp/swstats_cpu.h
>> index 26a2f462..bb178a04 100644
>> --- a/src/libcamera/software_isp/swstats_cpu.h
>> +++ b/src/libcamera/software_isp/swstats_cpu.h
>> @@ -18,9 +18,12 @@
>>  #include <libcamera/geometry.h>
>>  
>>  #include "libcamera/internal/bayer_format.h"
>> +#include "libcamera/internal/framebuffer.h"
>>  #include "libcamera/internal/shared_mem_object.h"
>>  #include "libcamera/internal/software_isp/swisp_stats.h"
>>  
>> +#include "benchmark.h"
>> +
>>  namespace libcamera {
>>  
>>  class PixelFormat;
>> @@ -42,6 +45,7 @@ public:
>>         void setWindow(const Rectangle &window);
>>         void startFrame();
>>         void finishFrame(uint32_t frame, uint32_t bufferId);
>> +       void processFrame(FrameBuffer *input);
>>  
>>         void processLine0(unsigned int y, const uint8_t *src[])
>>         {
>> @@ -77,6 +81,9 @@ private:
>>         void statsBGGR10PLine0(const uint8_t *src[]);
>>         void statsGBRG10PLine0(const uint8_t *src[]);
>>  
>> +       void processFrame2(const uint8_t *src);
>> +       void processFrame4(const uint8_t *src);
>> +
>>         /* Variables set by configure(), used every line */
>>         statsProcessFn stats0_;
>>         statsProcessFn stats2_;
>> @@ -89,9 +96,12 @@ private:
>>         Size patternSize_;
>>  
>>         unsigned int xShift_;
>> +       unsigned int bpp_; /* Memory used per pixel, not precision */
>> +       unsigned int stride_;
>>  
>>         SharedMemObject<SwIspStats> sharedStats_;
>>         SwIspStats stats_;
>> +       Benchmark bench_;
>>  };
>>  
>>  } /* namespace libcamera */
>> -- 
>> 2.46.2
>>
>