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<p>Hi all.</p>
<p>I think there might be a problem in the settingd of the VUI.</p>
<p>say we want to use - 10 fps.</p>
<p>We set <strong>timing_info_present_flag = 1</strong></p>
<p>We set <strong>num_units_in_tick = 1000</strong></p>
<p>We set <strong>time_scale = 10000</strong></p>
<p>We set <strong>fixed_frame_rate_flag = 1</strong></p>
<p>also</p>
<p>We set <strong>pic_struct_present_flag = 0</strong></p>
<p>We set <strong>field_pic_flag = 0</strong></p>
<p>from <strong>table E-6</strong> in the standard It derives ==> <strong>DeltaTfiDivisor = 2</strong> </p>
<p>I think ( and I see some players working that way ) that if a decoder</p>
<p>was to be working by the standard it would translate this to <strong>5 fps rather then 10</strong>.</p>
<p>here is why:</p>
<p>from the standard:</p>
<p>When fixed_frame_rate_flag is equal to 1, for all n where n indicates the n-th picture in output order and picture n is not</p>
<p>the last picture in the bitstream in output order, the value of <strong>Dtfi,dpb( n )</strong> as specified in Equation C-13, shall obey the</p>
<p>following constraint,</p>
<p><strong>Dtfi,dpb( n )</strong> = = <strong>Dto,dpb( n )</strong> / DeltaTfiDivisor (1)</p>
<p><strong>Dtfi,dpb( n )</strong> = num_units_in_tick / time_scale. (2)</p>
<p>from this If we calculate <strong>Dto,dpb( n )</strong> we get <strong>Dto,dpb( n )</strong> = (num_units_in_tick / time_scale) * 2 this is twice the <strong>Dto,dpb( n )</strong> we ment</p>
<p>and thus half the frame rate.</p>
<p>Am I correct? </p>
<p> ( all this is from pages 249 , 250 in <b><font face="Times New Roman" size="2">DRAFT ITU-T Rec. H.264 (2002 E) )</font></b></p></font>
<p>remaider - (C-13) --> Dto,dpb( n ) = to,dpb( nn ) - to,dpb( n )</p>
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