Function avifEncoderAddImageItems

src/write.c:1250–1291

Adds the items for a single cell or a grid of cells. Outputs the topLevelItemID which is the only item if there is exactly one cell, or the grid item for multiple cells. Note: The topLevelItemID output argument has the type uint16_t* instead of avifEncoderItem** because the avifEncoderItem pointer may be invalidated by a call to avifEncoderDataCreateItem().

// Note: The topLevelItemID output argument has the type uint16_t* instead of avifEncoderItem** because
//       the avifEncoderItem pointer may be invalidated by a call to avifEncoderDataCreateItem().
static avifResult avifEncoderAddImageItems(avifEncoder * encoder,
                                           uint32_t gridCols,
                                           uint32_t gridRows,
                                           uint32_t gridWidth,
                                           uint32_t gridHeight,
                                           avifItemCategory itemCategory,
                                           uint16_t * topLevelItemID)
{
    const uint32_t cellCount = gridCols * gridRows;
    const char * infeName = getInfeName(itemCategory);
    const size_t infeNameSize = strlen(infeName) + 1;

    if (cellCount > 1) {
        avifEncoderItem * gridItem = avifEncoderDataCreateItem(encoder->data, "grid", infeName, infeNameSize, 0);
        AVIF_CHECKRES(avifWriteGridPayload(&gridItem->metadataPayload, gridCols, gridRows, gridWidth, gridHeight));
        gridItem->itemCategory = itemCategory;
        gridItem->gridCols = gridCols;
        gridItem->gridRows = gridRows;
        gridItem->gridWidth = gridWidth;
        gridItem->gridHeight = gridHeight;
        *topLevelItemID = gridItem->id;
    }

    for (uint32_t cellIndex = 0; cellIndex < cellCount; ++cellIndex) {
        avifEncoderItem * item =
            avifEncoderDataCreateItem(encoder->data, encoder->data->imageItemType, infeName, infeNameSize, cellIndex);
        AVIF_CHECKERR(item, AVIF_RESULT_OUT_OF_MEMORY);
        AVIF_CHECKRES(avifCodecCreate(encoder->codecChoice, AVIF_CODEC_FLAG_CAN_ENCODE, &item->codec));
        item->codec->csOptions = encoder->csOptions;
        item->codec->diag = &encoder->diag;
        item->itemCategory = itemCategory;
        item->extraLayerCount = encoder->extraLayerCount;

        if (cellCount > 1) {
            item->dimgFromID = *topLevelItemID;
            item->hiddenImage = AVIF_TRUE;
        } else {
            *topLevelItemID = item->id;
        }
    }
    return AVIF_RESULT_OK;
}

static avifResult avifEncoderCreateBitDepthExtensionItems(avifEncoder * encoder,
                                                          uint32_t gridCols,