When dependent scalar quantization is used, the selection of the quantizer depends on the decoding of the preceding transform coefficient, and the entropy decoding of the transform coefficient depends on the selection of the quantizer. In order to maintain high throughput in hardware implementation for transform coefficient entropy coding, various determination methods of a scalar quantizer are proposed. In one implementation, state transition and context model selection is based only on canonical coded bins. For example, the state transition may be based on the SIG, the sum of the gt1 and gt2 flags, the exclusive OR function of the SIG, gt1 and gt2 flags, or may be based only on the gt1 or gt2 flags. When a block of transform coefficients is coded, normal mode bins may be coded first in one or more scan passes, and residual bypass coded bins are grouped together in another one or more scan passes.
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