private ImageStateInfo InitializeFromSingleImage(CompressedAV1Image color, CompressedAV1Image alpha)
{
ulong mediaDataBoxContentSize = color.Data.ByteLength;
uint itemId = FirstItemId;
AvifWriterItem colorItem = AvifWriterItem.CreateFromImage(itemId, "Color", color, false);
itemId++;
this.PrimaryItemId = colorItem.Id;
this.items.Add(colorItem);
if (alpha != null)
{
AvifWriterItem alphaItem = AvifWriterItem.CreateFromImage(itemId, "Alpha", alpha, true);
itemId++;
alphaItem.ItemReferences.Add(new ItemReferenceEntryBox(alphaItem.Id, ReferenceTypes.AuxiliaryImage, this.PrimaryItemId));
this.AlphaItemId = alphaItem.Id;
this.items.Add(alphaItem);
mediaDataBoxContentSize += alpha.Data.ByteLength;
}
return(new ImageStateInfo(mediaDataBoxContentSize, itemId));
}
private ImageStateInfo InitializeFromImageGrid(IReadOnlyList <CompressedAV1Image> colorImages,
IReadOnlyList <CompressedAV1Image> alphaImages,
ImageGridMetadata imageGridMetadata)
{
ulong mediaDataBoxContentSize = 0;
uint itemId = FirstItemId;
List <uint> colorImageIds = new List <uint>(colorImages.Count);
List <uint> alphaImageIds = alphaImages != null ? new List <uint>(alphaImages.Count) : null;
for (int i = 0; i < colorImages.Count; i++)
{
CompressedAV1Image color = colorImages[i];
AvifWriterItem colorItem = AvifWriterItem.CreateFromImage(itemId, null, color, false);
itemId++;
colorImageIds.Add(colorItem.Id);
this.items.Add(colorItem);
mediaDataBoxContentSize += color.Data.ByteLength;
if (alphaImages != null)
{
CompressedAV1Image alpha = alphaImages[i];
AvifWriterItem alphaItem = AvifWriterItem.CreateFromImage(itemId, null, alpha, true);
itemId++;
alphaItem.ItemReferences.Add(new ItemReferenceEntryBox(alphaItem.Id, ReferenceTypes.AuxiliaryImage, colorItem.Id));
alphaImageIds.Add(alphaItem.Id);
this.items.Add(alphaItem);
mediaDataBoxContentSize += alpha.Data.ByteLength;
}
}
ulong gridDescriptorLength;
if (imageGridMetadata.OutputHeight > ushort.MaxValue || imageGridMetadata.OutputWidth > ushort.MaxValue)
{
gridDescriptorLength = ImageGridDescriptor.LargeDescriptorLength;
}
else
{
gridDescriptorLength = ImageGridDescriptor.SmallDescriptorLength;
}
AvifWriterItem colorGridItem = AvifWriterItem.CreateFromImageGrid(itemId, "Color", 0, gridDescriptorLength);
itemId++;
colorGridItem.ItemReferences.Add(new ItemReferenceEntryBox(colorGridItem.Id, ReferenceTypes.DerivedImage, colorImageIds));
this.PrimaryItemId = colorGridItem.Id;
this.items.Add(colorGridItem);
if (alphaImages != null)
{
// The ImageGridDescriptor is shared between the color and alpha image.
AvifWriterItem alphaGridItem = AvifWriterItem.CreateFromImageGrid(itemId, "Alpha", 0, gridDescriptorLength);
itemId++;
alphaGridItem.ItemReferences.Add(new ItemReferenceEntryBox(alphaGridItem.Id, ReferenceTypes.AuxiliaryImage, colorGridItem.Id));
alphaGridItem.ItemReferences.Add(new ItemReferenceEntryBox(alphaGridItem.Id, ReferenceTypes.DerivedImage, alphaImageIds));
this.AlphaItemId = alphaGridItem.Id;
this.items.Add(alphaGridItem);
}
return(new ImageStateInfo(mediaDataBoxContentSize, itemId));
}
