Difference between revisions of "HanProgressReportAugust08"

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(TODO)
(TODO)
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==== TODO ====
 
==== TODO ====
 +
* automatic adjustment of # of bricks loaded at each frame
 +
 
* revert to memory pool instead of pixel buffer object pool..
 
* revert to memory pool instead of pixel buffer object pool..
 
** re-add prefetching thread
 
** re-add prefetching thread

Revision as of 13:58, 26 August 2008

UP

Contents

Deadline

  • Aug/11/2008
    • new class restructuring
  • Sep/22/2008
    • deadline

TODO

  • automatic adjustment of # of bricks loaded at each frame
  • revert to memory pool instead of pixel buffer object pool..
    • re-add prefetching thread
    • implement budget based algorithm
  • mipmapped video support
   * measuring performance for each step
     - find bottlenecks
     - with preloaded data: 40~50 fps, 0.025 ~ 0.02 sec/frame
     - without preloading: around 10 fps, 0.1 sec/frame....:(
   * prefetching next frames
   * point of interest (check paper again)
   * prefetching bricks?
   * test on starcave by this weekend
  • multi-volume support
   * mesh generation - generating a mesh for multivolumes under one constraint - memory size
   * rendering - multi-volume rendering
         o new rendering algorithm: need to manage multi bricks overlaps with several bricks! 
   * time-series multivolume rendering - need to handle multi timesteps

26 Tu


  • 65MB/s in a starcave node
    • 11 bricks / frame

25 Mon


  • Measured data loading time: 0.1 sec/frame reading O(10) bricks
    • wrote a short program reading sequentially
      • took 137 seconds for 6.5GB, 1200 files of multi-resolution tornado data
      • 47MB/s :(
      • tested with files in local disk
      • with this number, there will be no benefit by prefetching..
  • HDD benchmark
  • HDD benchmark 2
  • Let's say we have 50MB/s bandwidth..
    • one brick is 128 * 128 * 3 byte = 48 KB
    • 50MB/s/(30 frames/s) = 1.66MB/frame = 34 bricks / frame if we *only* consider loading time..
  • Assume we need 0.025 second / frame for rendering + all the other steps
    • to achieve 30 frames / second, rendering time will take 0.75 seconds, what is left (0.25 seconds) can be used for data loading
    • as the data loading time is 4 times smaller than the first case,
    • 34 bricks/frame/4 = 8 bricks / frame

12 Tues


  • we can control the quality of image rendered
    • parameterize voxel to pixel ratio
    • parameterize the total number of bricks loaded at each frame
  • need more performance measurements...

10 Sun


  • reimplemented covise plugin with the new MipMapVideoLib
  • tested on covise
    • 30 fps when cached
    • below 10 fps when first played

09 Sat


  • tested with 750 frames
    • 2M pixel screen
    • horrible performance 3~5 fps without caching
    • second run (with cache) achieves around 30~50 frames per second

08 Fri


  • debugged the bug
  • tested with 200 tornado data frames and it plays interactively
    • nearest neighbor interpolation causes lots of aliasing especially on lines and edges
    • no prefetching or asynchronous I/O was used
    • trying to come up with an algorithm that limits the total number of bricks loaded at each frame
      • heuristic. there can be a smarter algorithm than one in octreemizer..
      • don't know how much this would impact the overall performance
  • generating 600 frames

07 Thur


  • refine and debug frame window
    • debugging frame window..
    • data isn't changing...

06 Weds


Done

  • generated tornado tiff data sets
  • implemented frame window - need test!!!!!
    • opening next 10 frames
    • closing previous 10 frames
    • activating/deactivating BrickReaders
  • grpof to find bottlenecks
    • no bad calls, which means my system is IO bounded. =(

August/05/2008 (Tu)


  • multi-volume support
   * user interface - need to be able to manipulate one volume at a time
   * new class structures? like in virvo/multirend
  • dynamic change in volume control UI
    • hide/show according to volume selection

August/01/2008 (Fri)


Done

  • finalized the interface between MipMapVideo library and GUI part