fg(4.2) Comparative performances of reconstruction times with different graphic cards. Reconstruction times One of the largest process in Cyber is dedicated to reconstruction. This task uses massively graphic card features (...)">
Comparative performances of reconstruction times with different graphic cards.
One of the largest process in Cyber is dedicated to reconstruction. This task uses massively graphic card features and is done in following steps:
Percentage of time usage on each reconstruction step:
sgi IR3 (1RM) | sgi IR3 (2RM) | sgi Tezro V12 | GeForce4800tiSE | |||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
ReadTextures [A] | <1ms | <1ms | <1ms | <1ms | ||||||||||||||||||||||||||||||||
DrawQuads [B] |
|
|
|
|
||||||||||||||||||||||||||||||||
ReadPixels [C] | 5ms (RED) | <3ms (RED) | 6ms (RGBA) | 3 ms (RGB332*) | ||||||||||||||||||||||||||||||||
CreateVoxels [D] (CPU) | 4ms | 4ms | 3ms | 1ms | ||||||||||||||||||||||||||||||||
Total time for reconstruction with 4 cameras [A,B,C,D] |
14ms | 10-11ms | 55ms | < 5ms |
(configs: IR3=R12,G12,B12,A12,Depth31 - TezroV12=R4,G4,B4,A4,Depth24)
* RGB332 mode allow reading 3 voxels (drawn in R,G and B channels) in a single byte. Without this optimisation, this step would take twice time.
The time for renderings quads on V12 platform is very important due to 4bits per composant framebuffer(!!!!!!, it’s the “best” mode available with a double buffer, depth and alpha..., while the IR3 has 12bits per composant!).
Following table gives times (in milliseconds) for reading back a block of 512x512 pixels freom GPU to RAM (corresponding to a voxelic space of size 64x64x64):
config | R, G, B ou A | LUMINANCE | RGB | RGBA | BGR ou BGRA —>|
---|---|---|---|---|---|
Onyx R12000+IR3 (1RM) |
4.2 | <script language="javascript"> 6.9 | <script language="javascript"> 7.1 | <script language="javascript"> 7.0 | X—>|
Onyx R12000+IR3 (2RM) | <script language="javascript"> 2.4 | <script language="javascript"> 6.3 | <script language="javascript"> 6.3 | <script language="javascript"> 6.3 | X —>|
Tezro R16000+V12 | <script language="javascript"> 27.0 | <script language="javascript"> 28.0 | <script language="javascript"> 31.0 | <script language="javascript"> 7.2 | 35 —>|
? titre comparatif | |||||
PIV 1.6Ghz+Gf2MX | <script language="javascript"> 5.7 | <script language="javascript"> 55.0 | <script language="javascript"> 6.0 | <script language="javascript"> 5.5 | X —>|
Bi-PIII 933Mhz+Radeon9700 | <script language="javascript"> 6.9 | <script language="javascript"> 134.0 | <script language="javascript"> 22.2 | <script language="javascript"> 23.0 | X —>|
Bi-Xeon2.4Ghz+GF4800tiSE | <script language="javascript"> 5.0 | <script language="javascript"> 35.0 | <script language="javascript"> 5.0 | <script language="javascript"> 5.0 | X —>