process_pipeline: Store a default whitelevel in the DNG file

This helps unpacked 10-bit formats, as otherwise applications
assume the image to be 16-bit because of TIFFTAG_BITSPERSAMPLE.

src/camera.c

@@ -122,6 +122,28 @@ mp_pixel_format_bits_per_pixel(MPPixelFormat pixel_format)
 	}
 }
 
+uint32_t
+mp_pixel_format_pixel_depth(MPPixelFormat pixel_format)
+{
+	g_return_val_if_fail(pixel_format < MP_PIXEL_FMT_MAX, 0);
+	switch (pixel_format) {
+	case MP_PIXEL_FMT_BGGR8:
+	case MP_PIXEL_FMT_GBRG8:
+	case MP_PIXEL_FMT_GRBG8:
+	case MP_PIXEL_FMT_RGGB8:
+	case MP_PIXEL_FMT_UYVY:
+	case MP_PIXEL_FMT_YUYV:
+		return 8;
+	case MP_PIXEL_FMT_GBRG10P:
+	case MP_PIXEL_FMT_GRBG10P:
+	case MP_PIXEL_FMT_RGGB10P:
+	case MP_PIXEL_FMT_BGGR10P:
+		return 10;
+	default:
+		return 0;
+	}
+}
+
 uint32_t
 mp_pixel_format_width_to_bytes(MPPixelFormat pixel_format, uint32_t width)
 {