internal static unsafe void EncodeWebP(Stream writer, Texture2D texture, bool lossless, float quality)
{
bool hasAlpha = HasAlpha(texture);
// Stream stream = fileInfo.Create();
var format = hasAlpha ? UnityEngine.TextureFormat.RGBA32 : UnityEngine.TextureFormat.RGB24;
var outputTexture = BlitTexture(texture, format);
WebPConfig config = new WebPConfig();
WebPPicture picture = new WebPPicture();
if (WebpEncoderNativeCalls.WebPConfigInitInternal(ref config, WebPPreset.WEBP_PRESET_DEFAULT, quality, WEBP_ENCODER_ABI_VERSION) == 0)
{
throw new Exception("Failed to initialize WebPConfig.");
}
if (lossless)
{
//TODO: refine the level value [0..9] we want to set. 6 seems a good default value
WebpEncoderNativeCalls.WebPConfigLosslessPreset(ref config, 6);
}
if (WebpEncoderNativeCalls.WebPValidateConfig(ref config) == 0)
{
throw new Exception("Failed to validate WebPConfig.");
}
if (WebpEncoderNativeCalls.WebPPictureInitInternal(ref picture, WEBP_ENCODER_ABI_VERSION) == 0)
{
throw new Exception("Failed to initialize WebPPicture, version mismatch."); // version mismatch error
}
picture.width = outputTexture.width;
picture.height = outputTexture.height;
if (WebpEncoderNativeCalls.WebPPictureAlloc(ref picture) == 0)
{
throw new Exception("Failed to allocate WebPPicture");
}
GCHandle lPinnedArray = GCHandle.Alloc(outputTexture.GetRawTextureData(), GCHandleType.Pinned);
fixed(byte *buffer = outputTexture.GetRawTextureData())
{
if (hasAlpha)
{
int stride = picture.width * 4;
byte *lTmpDataPtr = buffer + (picture.height - 1) * stride;
WebpEncoderNativeCalls.WebPPictureImportRGBA(ref picture, lTmpDataPtr, -stride);
}
else
{
int stride = picture.width * 3;
byte *lTmpDataPtr = buffer + (picture.height - 1) * stride;
WebpEncoderNativeCalls.WebPPictureImportRGB(ref picture, lTmpDataPtr, -stride);
}
}
//Write the compressed data in WebPWriterFunction
picture.writer = (IntPtr data, UIntPtr size, ref WebPPicture pPicture) =>
{
byte[] res = new byte[size.ToUInt32()];
Marshal.Copy(data, res, 0, (int)size.ToUInt32());
try
{
writer.Write(res, 0, res.Length);
}
catch (Exception e)
{
throw new Exception("Failed in writing a WebP compressed image to a stream." + e.Message);
}
return(1);
};
if (WebpEncoderNativeCalls.WebPEncode(ref config, ref picture) == 0)
{
WebpEncoderNativeCalls.WebPPictureFree(ref picture);
throw new Exception($"Failed to encode webp image error: {picture.error_code.ToString()}");
}
WebpEncoderNativeCalls.WebPPictureFree(ref picture);
writer.Dispose();
lPinnedArray.Free();
}
internal int MyFileWriter([In] IntPtr data, [param: MarshalAs(UnmanagedType.SysUInt)] UIntPtr data_size, ref WebPPicture picture)
{
int blocksize = (int)data_size;
if (this._preallocateOnDisk)
{
this._preallocateOnDisk = false;
// The first memory block that decoder push will be the webp file header (which contains the WebPContent size in bytes).
// Total of 12 bytes:
// 4: ASCII "RIFF"
// 4: WebP Content Size
// 4: ASCII "WEBP"
// Get the WebPContent size in bytes
int contentSizeWithoutRIFFHeader = Marshal.ReadInt32(data, 4);
contentSizeWithoutRIFFHeader += 8; // Because the we got above is starting from offset 8 of the real file.
try
{
this.fs.SetLength(contentSizeWithoutRIFFHeader);
}
catch
{
// Pre-allocate size on disk failed. Either not enough space or I don't know.
return(0);
}
}
unsafe
{
byte *b = (byte *)(data.ToPointer());
try
{
for (int i = 0; i < blocksize; i++)
{
// WriteByte may cause overhead but Marshal.Copy to use Write(byte[], int, int) is not good in case, either.
// WriteByte method still uses FileStream's buffer, by the way.
this.fs.WriteByte(b[i]);
}
}
catch
{
// Tell the native library to stop because we got an error here.
// Either the file has been removed or the write permission has been cut off by someone (in case it's a network file)
// Or locked by anti-virus or anything.
return(0);
}
}
return(1);
}