On Thu, 12 Oct 2006, Balaji Raman wrote: > I want to count the number of bits for each macroblock after VLD and IQ > task execution, also I want to count the number of bits for each > macroblock after IDCT and MC execution. Can you advice me how to do > this?
Hi Balaji, Sounds fun! You should be able to do this by instrumenting libmpeg2/slice.c. Correct me if I'm wrong, though, but are your quantities really that interesting/well-defined? The output of inverse quantization (your first quantity) is a matrix of 12-bit integer coefficients (clause 7.4.3). Isn't the size of this matrix (for a coded macroblock) just going to be the reconstructed size of the macroblock -- e.g., 8 * 8 * 6 elements for 4:2:0? If so, every coded 4:2:0 macroblock is 12 * 8 * 8 * 6 bits at this stage -- not very interesting. You'd also have to add in the coded length of the as-yet-undecoded motion vectors (which, in fairness, require reference to previous macroblocks to decode; see cl. 7.6.3.1). Your second quantity also seems unlikely to be that interesting if I understand you correctly. After you've done motion prediction, what left is there to do? You're done. The final decoded samples are just a matrix of 8-bit numbers (see cl. 7.6.8) the size of the reconstructed macroblock (e.g., 8 * 8 * 6 elements for 4:2:0). So a decoded 4:2:0 macroblock is always 8 * 8 * 8 * 6 bits. So, if I understand you correctly, your first quantity is always just the length of the motion_vectors() in the macroblock() plus 4,608 (for coded 4:2:0 macroblocks), and your second quantity is always 3,072 (for 4:2:0 macroblocks with restricted slice structure). Where am I going wrong? -Keith ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ Libmpeg2-devel mailing list Libmpeg2-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libmpeg2-devel
