[Mp4-tech] MPEG4 Simple Profile question. Is DC/AC saturation in the range [-2048, 2047] redundant provided that bits_per_pixel is 8?

[Shevach Riabtsev]

Dear experts 
I have a question on MPEG4 Simple Profile related to DC/AC quantized
coefficient saturation. 
According to 7.4.3.4 
The quantized coefficients resulting from the DC and AC Prediction are
saturated to lie in the range [-2048, 2047].
In MPEG4 Simple Profile bits_per_pixel value is 8, I don't see a case
when a quantized DC or AC coefficient can exceed [-2048,2047] range. 
For example,  DC obtains the maximal value equal 8*255 = 2040 provided
that all pixels in a 8x8 block are 255, see A.1. The minimal DC
quantization scaler is 8 (see Table 7-1). Thus the maximal quantized DC
magnitude is 2040/8=255. Hence DC residual lies in the interval
[-255..255].  The same reasoning can be applied to AC case. 
Thus I conjecture that AC/DC coefficients satuaration is redundant in
Simple Profile. Am I right?
Regards, Shevach 
Broadcom
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