A system includes code including first obtaining code to obtain a first syntax element that indicates a first quantization index value for an AC coefficient of an image; second obtaining code to obtain at least one second syntax element that indicates an offset value; third obtaining code to obtain a second quantization index value for another coefficient of the image; fourth obtaining code to obtain a quantization step size that corresponds to the second quantization index value that is obtained; and determining code to determine whether a mode in which the image is to be coded is a lossy mode or a lossless mode based on determining whether the first quantization index value is equal to a quantization index value associated with lossless coding, and based on determining whether the offset value is less than or equal to the quantization index value associated with the lossless coding.