1. 27 Jul, 2013 1 commit
    • Jingning Han's avatar
      Shortcut 8x8/16x16 inverse 2D-DCT · 38fa4871
      Jingning Han authored
      This commit brought back the shortcut implementation of 8x8/16x16
      inverse 2D-DCT. When the eob <= 10, it skips the inverse transform
      operations on row 4:7/4:15 in the first round. For bus_cif at 1000
      kbps, this provides about 2% speed-up at speed 0.
      
      Change-Id: I453e2d72956467d75be4ad8c04b4482ab889d572
      38fa4871
  2. 26 Jul, 2013 2 commits
    • Jingning Han's avatar
      Special handle on DC only inverse 8x8 2D-DCT · 325e0aa6
      Jingning Han authored
      This commit enables a special handle for the 8x8 inverse 2D-DCT,
      where only DC coefficient is quantized to be non-zero. For bus_cif
      at 2000 kbps, it provides about 1% speed-up at speed 0.
      
      Change-Id: I2523222359eec26b144cf8fd4c63a4ad63b1b011
      325e0aa6
    • Yunqing Wang's avatar
      Modify static threshold calculation · 52256cdb
      Yunqing Wang authored
      Used 3 * standard_deviation in internal threshold calculation
      instead of fit curve. This actually approached the algorithm
      better.
      For comparison, similar tests were done:
      The overall psnr loss is less than before.
      1. derf set:
      when static-thresh = 1, psnr loss is 0.329%;
      when static-thresh = 500, psnr loss is 0.970%;
      2. stdhd set:
      when static-thresh = 1, psnr loss is 0.922%;
      when static-thresh = 500, psnr loss is 1.307%;
      
      Similar speedup is achieved. For example,
      clip            bitrate  static-thresh psnr    time
      akiyo(cif)       500        0          48.952  5.077s(50f)
      akiyo            500        500        48.866  4.169s(50f)
      
      parkjoy(1080p)   4000       0          30.388  78.20s(30f)
      parkjoy          4000       500        30.367  70.85s(30f)
      
      sunflower(1080p) 4000       0          44.402  74.55s(30f)
      sunflower        4000       500        44.414  68.69s(30f)
      
      Change-Id: Ic78833642ce1911dbbd1cb6c899a2d7e2dfcc1f3
      52256cdb
  3. 25 Jul, 2013 26 commits
  4. 24 Jul, 2013 11 commits