Function avifDecoderGenerateImageGridTiles

src/read.c:1696–1730

Creates the tiles and associate them to the items in the order of the 'dimg' association.

// Creates the tiles and associate them to the items in the order of the 'dimg' association.
static avifResult avifDecoderGenerateImageGridTiles(avifDecoder * decoder,
                                                    avifDecoderItem * gridItem,
                                                    avifItemCategory itemCategory,
                                                    const uint32_t * dimgIdxToItemIdx,
                                                    uint32_t numTiles)
{
    avifBool progressive = AVIF_TRUE;
    for (uint32_t dimgIdx = 0; dimgIdx < numTiles; ++dimgIdx) {
        const uint32_t itemIdx = dimgIdxToItemIdx[dimgIdx];
        AVIF_ASSERT_OR_RETURN(itemIdx < gridItem->meta->items.count);
        avifDecoderItem * item = gridItem->meta->items.item[itemIdx];

        const avifCodecType tileCodecType = avifGetCodecType(item->type);
        AVIF_CHECKERR(tileCodecType != AVIF_CODEC_TYPE_UNKNOWN, AVIF_RESULT_INVALID_IMAGE_GRID);
        const avifTile * tile =
            avifDecoderDataCreateTile(decoder->data, tileCodecType, item->width, item->height, avifDecoderItemOperatingPoint(item));
        AVIF_CHECKERR(tile != NULL, AVIF_RESULT_OUT_OF_MEMORY);
        AVIF_CHECKRES(avifCodecDecodeInputFillFromDecoderItem(tile->input,
                                                              item,
                                                              decoder->allowProgressive,
                                                              decoder->imageCountLimit,
                                                              decoder->io->sizeHint,
                                                              &decoder->diag));
        tile->input->itemCategory = itemCategory;

        if (!item->progressive) {
            progressive = AVIF_FALSE;
        }
    }
    if (itemCategory == AVIF_ITEM_COLOR && progressive) {
        // If all the items that make up the grid are progressive, then propagate that status to the top-level grid item.
        gridItem->progressive = AVIF_TRUE;
    }
    return AVIF_RESULT_OK;
}

// Allocates the dstImage. Also verifies some spec compliance rules for grids, if relevant.
static avifResult avifDecoderDataAllocateImagePlanes(const avifDecoderData * data, const avifTileInfo * info, avifImage * dstImage, avifBool * cicpSet)