[libcamera-devel] [PATCH 3/3] utils: raspberrypi: ctt: dng_load_image: Work with DNG files from Picamera2

[David Plowman]

Hi William

Thanks very much for fixing this!

On Wed, 6 Jul 2022 at 11:18, David Plowman
<david.plowman at raspberrypi.com> wrote:
>
> From: William Vinnicombe <william.vinnicombe at raspberrypi.com>
>
> The exif tags are different between raw files from libcamera-apps and
> from Picamera2, causing issues loading data.
>
> Add code to identify which tags are being used, and then load the
> metadata from the correct tags.
>
> Signed-off-by: William Vinnicombe <william.vinnicombe at raspberrypi.com>

Reviewed-by: David Plowman <david.plowman at raspberrypi.com>

Thanks!
David

> ---
>  utils/raspberrypi/ctt/ctt_image_load.py | 26 ++++++++++++++++++-------
>  1 file changed, 19 insertions(+), 7 deletions(-)
>
> diff --git a/utils/raspberrypi/ctt/ctt_image_load.py b/utils/raspberrypi/ctt/ctt_image_load.py
> index 934db123..29c17581 100644
> --- a/utils/raspberrypi/ctt/ctt_image_load.py
> +++ b/utils/raspberrypi/ctt/ctt_image_load.py
> @@ -301,17 +301,29 @@ def dng_load_image(Cam, im_str):
>          metadata.read()
>
>          Img.ver = 100  # random value
> -        Img.w = metadata['Exif.SubImage1.ImageWidth'].value
> +        """
> +        libcamera-apps create a separate Exif.Subimage1 for the picture
> +        picamera2 stores everything under Exif.Image
> +        this code detects which one is being used, and therefore extracts the correct values
> +        """
> +        try:
> +            Img.w = metadata['Exif.SubImage1.ImageWidth'].value
> +            subimage = "SubImage1"
> +            photo = "Photo"
> +        except KeyError:
> +            Img.w = metadata['Exif.Image.ImageWidth'].value
> +            subimage = "Image"
> +            photo = "Image"
>          Img.pad = 0
> -        Img.h = metadata['Exif.SubImage1.ImageLength'].value
> -        white = metadata['Exif.SubImage1.WhiteLevel'].value
> +        Img.h = metadata[f'Exif.{subimage}.ImageLength'].value
> +        white = metadata[f'Exif.{subimage}.WhiteLevel'].value
>          Img.sigbits = int(white).bit_length()
>          Img.fmt = (Img.sigbits - 4) // 2
> -        Img.exposure = int(metadata['Exif.Photo.ExposureTime'].value*1000000)
> -        Img.againQ8 = metadata['Exif.Photo.ISOSpeedRatings'].value*256/100
> +        Img.exposure = int(metadata[f'Exif.{photo}.ExposureTime'].value*1000000)
> +        Img.againQ8 = metadata[f'Exif.{photo}.ISOSpeedRatings'].value*256/100
>          Img.againQ8_norm = Img.againQ8 / 256
>          Img.camName = metadata['Exif.Image.Model'].value
> -        Img.blacklevel = int(metadata['Exif.SubImage1.BlackLevel'].value[0])
> +        Img.blacklevel = int(metadata[f'Exif.{subimage}.BlackLevel'].value[0])
>          Img.blacklevel_16 = Img.blacklevel << (16 - Img.sigbits)
>          bayer_case = {
>              '0 1 1 2': (0, (0, 1, 2, 3)),
> @@ -319,7 +331,7 @@ def dng_load_image(Cam, im_str):
>              '2 1 1 0': (2, (3, 2, 1, 0)),
>              '1 0 2 1': (3, (1, 0, 3, 2))
>          }
> -        cfa_pattern = metadata['Exif.SubImage1.CFAPattern'].value
> +        cfa_pattern = metadata[f'Exif.{subimage}.CFAPattern'].value
>          Img.pattern = bayer_case[cfa_pattern][0]
>          Img.order = bayer_case[cfa_pattern][1]
>
> --
> 2.30.2
>