Update PngDecoderCore.cs

JimBobSquarePants · JimBobSquarePants · commit 90fa81713529 · 2023-11-26T22:40:10.000+10:00
diff --git a/src/ImageSharp/Formats/Png/PngDecoderCore.cs b/src/ImageSharp/Formats/Png/PngDecoderCore.cs
@@ -765,7 +765,7 @@ private void DecodePixelData<TPixel>(
             cancellationToken.ThrowIfCancellationRequested();
             int bytesPerFrameScanline = this.CalculateScanlineLength((int)frameControl.Width) + 1;
             Span<byte> scanSpan = this.scanline.GetSpan()[..bytesPerFrameScanline];
-            Span<byte> prevSpan = this.scanline.GetSpan()[..bytesPerFrameScanline];
+            Span<byte> prevSpan = this.previousScanline.GetSpan()[..bytesPerFrameScanline];
 
             while (currentRowBytesRead < bytesPerFrameScanline)
             {

Original file line number	Diff line number	Diff line change
`@@ -765,7 +765,7 @@ private void DecodePixelData<TPixel>(`
`765`	`765`	`cancellationToken.ThrowIfCancellationRequested();`
`766`	`766`	`int bytesPerFrameScanline = this.CalculateScanlineLength((int)frameControl.Width) + 1;`
`767`	`767`	`Span<byte> scanSpan = this.scanline.GetSpan()[..bytesPerFrameScanline];`
`768`		`- Span<byte> prevSpan = this.scanline.GetSpan()[..bytesPerFrameScanline];`
	`768`	`+ Span<byte> prevSpan = this.previousScanline.GetSpan()[..bytesPerFrameScanline];`
`769`	`769`
`770`	`770`	`while (currentRowBytesRead < bytesPerFrameScanline)`
`771`	`771`	`{`