Bubble up the transferFunction value

ktx2Decoder/src/ktx2Decoder.ts

@@ -32,6 +32,7 @@ export interface IDecodedData {
     height: number;
     transcodedFormat: number;
     mipmaps: Array<IMipmap>;
+    isInGammaSpace: boolean;
     errors?: string;
 }
 
@@ -129,7 +130,7 @@ export class KTX2Decoder {
         const mipmaps: Array<IMipmap> = [];
         const dataPromises: Array<Promise<Nullable<Uint8Array>>> = [];
         const mipmapBuffers: Array<ArrayBuffer> = [];
-        const decodedData: IDecodedData = { width: 0, height: 0, transcodedFormat, mipmaps };
+        const decodedData: IDecodedData = { width: 0, height: 0, transcodedFormat, mipmaps, isInGammaSpace: kfr.isInGammaSpace };
 
         let firstImageDescIndex = 0;
 

ktx2Decoder/src/ktx2FileReader.ts

@@ -29,6 +29,11 @@ const enum dfdChannel_UASTC {
     RRRG = 5
 }
 
+const enum dfdTransferFunction {
+    linear = 1,
+    sRGB = 2
+}
+
 /** @hidden */
 export interface IKTX2_Header {
     vkFormat: number;
@@ -339,6 +344,10 @@ export class KTX2FileReader {
         return this._header.supercompressionScheme === supercompressionScheme.ZStandard;
     }
 
+    public get isInGammaSpace(): boolean {
+        return this._dfdBlock.transferFunction === dfdTransferFunction.sRGB;
+    }
+
     public static IsValid(data: ArrayBufferView): boolean {
         if (data.byteLength >= 12) {
             // '«', 'K', 'T', 'X', ' ', '2', '0', '»', '\r', '\n', '\x1A', '\n'