Read bits per sample

src/tiff/tiffread.h

@@ -123,6 +123,14 @@ struct tiff_alpha {
   u32 sample_offset;
 };
 
+typedef struct tiff_sample_bits TiffSampleBits;
+struct tiff_sample_bits {
+  u16 r;
+  u16 g;
+  u16 b;
+  u16 a;
+};
+
 typedef struct tiff_strip TiffStrip;
 struct tiff_strip {
   u32 offset;
@@ -152,6 +160,7 @@ struct tiff_image {
   u32 extra_samples_count;
   bool extra_samples_offset;
   TiffAlpha alpha;
+  TiffSampleBits rgba_bits_per_sample;
   TiffStrip *strips;
 };