[libcamera-devel] [PATCH] libcamera: PixelFormat: Define a FourCC output helper

[Kieran Bingham]

Hi Nicolas,

On 31/01/2020 15:20, Nicolas Dufresne wrote:
> Le jeudi 30 janvier 2020 à 21:38 +0000, Kieran Bingham a écrit :
>> Provide a helper to print the FourCC string representation, and utilise
>> it to improve the readability of the StreamConfiguration.
>>
>> Signed-off-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
>> ---
>> This changes the output of the line:
>> [159:34:26.262068766] [16497] INFO Camera camera.cpp:784 configuring streams: (0) 1920x1080-0x47504a4d
>>
>> to read:
>> [159:34:26.262068766] [16497] INFO Camera camera.cpp:784 configuring streams: (0) 1920x1080-0x47504a4d MJPG
> 
> Perhaps we could drop the hex form ? Is it really useful ?

Indeed it probably isn't!

I'll remove this as part of the respin to a class/struct as suggested by
Laurent.

--
Kieran


>>
>>  include/libcamera/pixelformats.h |  3 +++
>>  src/libcamera/pixelformats.cpp   | 20 ++++++++++++++++++++
>>  src/libcamera/stream.cpp         |  3 ++-
>>  3 files changed, 25 insertions(+), 1 deletion(-)
>>
>> diff --git a/include/libcamera/pixelformats.h b/include/libcamera/pixelformats.h
>> index 6e25b8d8b76e..32cff083cdf9 100644
>> --- a/include/libcamera/pixelformats.h
>> +++ b/include/libcamera/pixelformats.h
>> @@ -8,11 +8,14 @@
>>  #define __LIBCAMERA_PIXEL_FORMATS_H__
>>  
>>  #include <stdint.h>
>> +#include <string>
>>  
>>  namespace libcamera {
>>  
>>  using PixelFormat = uint32_t;
>>  
>> +std::string FourCC(const PixelFormat &p);
>> +
>>  } /* namespace libcamera */
>>  
>>  #endif /* __LIBCAMERA_PIXEL_FORMATS_H__ */
>> diff --git a/src/libcamera/pixelformats.cpp b/src/libcamera/pixelformats.cpp
>> index c03335400b70..d6b2c6a3dba5 100644
>> --- a/src/libcamera/pixelformats.cpp
>> +++ b/src/libcamera/pixelformats.cpp
>> @@ -7,6 +7,8 @@
>>  
>>  #include <libcamera/pixelformats.h>
>>  
>> +#include <sstream>
>> +
>>  /**
>>   * \file pixelformats.h
>>   * \brief libcamera pixel formats
>> @@ -25,4 +27,22 @@ namespace libcamera {
>>   * \todo Add support for format modifiers
>>   */
>>  
>> +/**
>> + * \brief Return a PixelFormat as a FourCC string representation
>> + */
>> +std::string FourCC(const PixelFormat &p)
>> +{
>> +	std::stringstream ss;
>> +
>> +	ss << static_cast<char>(p & 0x7f)
>> +	   << static_cast<char>((p >> 8) & 0x7f)
>> +	   << static_cast<char>((p >> 16) & 0x7f)
>> +	   << static_cast<char>((p >> 24) & 0x7f);
>> +
>> +	if (p & (1 << 31))
>> +		ss << "-BE";
>> +
>> +	return ss.str();
>> +}
>> +
>>  } /* namespace libcamera */
>> diff --git a/src/libcamera/stream.cpp b/src/libcamera/stream.cpp
>> index 13789e9eb344..4efe4385326f 100644
>> --- a/src/libcamera/stream.cpp
>> +++ b/src/libcamera/stream.cpp
>> @@ -348,7 +348,8 @@ StreamConfiguration::StreamConfiguration(const StreamFormats &formats)
>>  std::string StreamConfiguration::toString() const
>>  {
>>  	std::stringstream ss;
>> -	ss << size.toString() << "-" << utils::hex(pixelFormat);
>> +	ss << size.toString() << "-" << utils::hex(pixelFormat)
>> +	   << " " << FourCC(pixelFormat);
>>  	return ss.str();
>>  }
>>  
> 

-- 
Regards
--
Kieran