[PATCH 2/2] apps: common: dng_writer: Fix RAW10 and RAW12 packing on BE machines

[Umang Jain]

Hi Laurent,

Thank you for the patch.

On 29/06/24 3:05 am, Laurent Pinchart wrote:
> The 16-bit padded raw 10 and raw 12 formats are stored in memory in
> little endian order, regardless of the machine's endianness. Read pixel
> data as uint8_t values and hardcode bit shifting to little endian to fix
> scanline packing.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

Reviewed-by: Umang Jain <umang.jain at ideasonboard.com>

> ---
>   src/apps/common/dng_writer.cpp | 24 ++++++++++++------------
>   1 file changed, 12 insertions(+), 12 deletions(-)
>
> diff --git a/src/apps/common/dng_writer.cpp b/src/apps/common/dng_writer.cpp
> index 50db5eb33c83..355433b08d68 100644
> --- a/src/apps/common/dng_writer.cpp
> +++ b/src/apps/common/dng_writer.cpp
> @@ -139,29 +139,29 @@ void packScanlineRaw8(void *output, const void *input, unsigned int width)
>   
>   void packScanlineRaw10(void *output, const void *input, unsigned int width)
>   {
> -	const uint16_t *in = static_cast<const uint16_t *>(input);
> +	const uint8_t *in = static_cast<const uint8_t *>(input);
>   	uint8_t *out = static_cast<uint8_t *>(output);
>   
>   	for (unsigned int i = 0; i < width; i += 4) {
> -		*out++ = (in[0] & 0x3fc) >> 2;
> -		*out++ = (in[0] & 0x003) << 6 | (in[1] & 0x3f0) >> 4;
> -		*out++ = (in[1] & 0x00f) << 4 | (in[2] & 0x3c0) >> 6;
> -		*out++ = (in[2] & 0x03f) << 2 | (in[3] & 0x300) >> 8;
> -		*out++ = (in[3] & 0x0ff);
> -		in += 4;
> +		*out++ = in[1] << 6 | in[0] >> 2;
> +		*out++ = in[0] << 6 | (in[3] & 0x03) << 4 | in[2] >> 4;
> +		*out++ = in[2] << 4 | (in[5] & 0x03) << 2 | in[4] >> 6;
> +		*out++ = in[4] << 2 | (in[7] & 0x03) << 0;
> +		*out++ = in[6];
> +		in += 8;
>   	}
>   }
>   
>   void packScanlineRaw12(void *output, const void *input, unsigned int width)
>   {
> -	const uint16_t *in = static_cast<const uint16_t *>(input);
> +	const uint8_t *in = static_cast<const uint8_t *>(input);
>   	uint8_t *out = static_cast<uint8_t *>(output);
>   
>   	for (unsigned int i = 0; i < width; i += 2) {
> -		*out++ = (in[0] & 0xff0) >> 4;
> -		*out++ = (in[0] & 0x00f) << 4 | (in[1] & 0xf00) >> 8;
> -		*out++ = (in[1] & 0x0ff);
> -		in += 2;
> +		*out++ = in[1] << 4 | in[0] >> 4;
> +		*out++ = in[0] << 4 | (in[3] & 0x0f);
> +		*out++ = in[2];
> +		in += 4;
>   	}
>   }
>