Fix issue with resizing the bitwriter buffer

src/ImageSharp/Formats/WebP/BitWriter/BitWriterBase.cs

@@ -61,13 +61,8 @@ namespace SixLabors.ImageSharp.Formats.Webp.BitWriter
         /// <param name="height">The height of the image.</param>
         public abstract void WriteEncodedImageToStream(Stream stream, ExifProfile exifProfile, uint width, uint height);
 
-        protected bool ResizeBuffer(int maxBytes, int sizeRequired)
+        protected void ResizeBuffer(int maxBytes, int sizeRequired)
         {
-            if (maxBytes > 0 && sizeRequired < maxBytes)
-            {
-                return true;
-            }
-
             int newSize = (3 * maxBytes) >> 1;
             if (newSize < sizeRequired)
             {
@@ -77,8 +72,6 @@ namespace SixLabors.ImageSharp.Formats.Webp.BitWriter
             // Make new size multiple of 1k.
             newSize = ((newSize >> 10) + 1) << 10;
             Array.Resize(ref this.buffer, newSize);
-
-            return false;
         }
 
         /// <summary>

src/ImageSharp/Formats/WebP/BitWriter/Vp8LBitWriter.cs

@@ -43,14 +43,14 @@ namespace SixLabors.ImageSharp.Formats.Webp.BitWriter
         /// </summary>
         private int cur;
 
-        private int end;
-
         /// <summary>
         /// Initializes a new instance of the <see cref="Vp8LBitWriter"/> class.
         /// </summary>
         /// <param name="expectedSize">The expected size in bytes.</param>
         public Vp8LBitWriter(int expectedSize)
-            : base(expectedSize) => this.end = this.Buffer.Length;
+            : base(expectedSize)
+        {
+        }
 
         /// <summary>
         /// Initializes a new instance of the <see cref="Vp8LBitWriter"/> class.
@@ -184,9 +184,9 @@ namespace SixLabors.ImageSharp.Formats.Webp.BitWriter
         private void PutBitsFlushBits()
         {
             // If needed, make some room by flushing some bits out.
-            if (this.cur + WriterBytes > this.end)
+            if (this.cur + WriterBytes > this.Buffer.Length)
             {
-                int extraSize = this.end - this.cur + MinExtraSize;
+                int extraSize = this.Buffer.Length - this.cur + MinExtraSize;
                 this.BitWriterResize(extraSize);
             }
 
@@ -204,15 +204,9 @@ namespace SixLabors.ImageSharp.Formats.Webp.BitWriter
         /// <param name="extraSize">The extra size in bytes needed.</param>
         public override void BitWriterResize(int extraSize)
         {
-            int maxBytes = this.end + this.Buffer.Length;
+            int maxBytes = this.Buffer.Length + this.Buffer.Length;
             int sizeRequired = this.cur + extraSize;
-
-            if (this.ResizeBuffer(maxBytes, sizeRequired))
-            {
-                return;
-            }
-
-            this.end = this.Buffer.Length;
+            this.ResizeBuffer(maxBytes, sizeRequired);
         }
     }
 }

tests/ImageSharp.Tests/Formats/WebP/WebpEncoderTests.cs

@@ -64,6 +64,7 @@ namespace SixLabors.ImageSharp.Tests.Formats.Webp
         [WithFile(Lossy.NoFilter06, PixelTypes.Rgba32, 4, 100)]
         [WithFile(Lossy.NoFilter06, PixelTypes.Rgba32, 5, 100)]
         [WithFile(Lossy.NoFilter06, PixelTypes.Rgba32, 6, 100)]
+        [WithFile(TestImages.Png.BikeSmall, PixelTypes.Rgba32, 6, 100)]
         public void Encode_Lossless_WithDifferentMethodAndQuality_Works<TPixel>(TestImageProvider<TPixel> provider, int method, int quality)
             where TPixel : unmanaged, IPixel<TPixel>
         {

tests/ImageSharp.Tests/TestImages.cs

@@ -44,6 +44,7 @@ namespace SixLabors.ImageSharp.Tests
             public const string CalliphoraPartial = "Png/CalliphoraPartial.png";
             public const string CalliphoraPartialGrayscale = "Png/CalliphoraPartialGrayscale.png";
             public const string Bike = "Png/Bike.png";
+            public const string BikeSmall = "Png/bike-small.png";
             public const string BikeGrayscale = "Png/BikeGrayscale.png";
             public const string SnakeGame = "Png/SnakeGame.png";
             public const string Icon = "Png/icon.png";