DivX HEVC Hardware Acceleration: Test Results on Intel Skylake

Enabling DivX Accelerated Options

The DivX Accelerated program vigorously tests and validates that a particular chipset is optimized for decoding and/or encoding of DivX video formats in DivX Software. Until now, DivX Software has offered DivX Accelerated functionality for encoding and decoding of AVC video (H.264/MKV and MP4) and decoding of AVI video (DivX/MPEG-4 ASP).

As of the DivX 10.4 software release, Intel® Quick Sync Video has been enabled natively to the new DivX Player to enable hardware accelerated decoding of HEVC video on computers with supported Intel chipsets. You can enable the DivX Accelerated option in Player’s Preferences.

This is a significant milestone to improve the experience of playing HEVC video, especially at high resolutions like 4K. This experience is particularly improved on the newly released 6th Generation Intel Core processor family (“Skylake”), which uses the dedicated media processing capabilities of Intel Graphics Technology.

The 4th and 5th Generations Intel Core Processor families (“Haswell” and “Broadwell”) offer a form of improved HEVC video playback through partial hardware acceleration support. However, the 6th Generation Intel processors offers full fixed-function decode through Intel® Quick Sync Video that offers high performance decode while also enabling the processor to complete other tasks, improving overall PC performance and responsiveness.

Our preliminary tests below performed on an engineering-build Skylake 2-in-1 laptop confirm these findings. In our testing of 4K HEVC video for CPU Performance, Memory Usage and Frames per Second, all were significantly improved when DivX Accelerated was on compared to the same tests with DivX Accelerated turned off.

DivX265 HEVC Command Line Encoder evaluation

This post details the results of our comparison of the latest version of DivX265 encoder v 1.5, our HEVC command line encoder with HM (HEVC reference encoder), x265 v 1.6 and x264. HEVC test stream Kimono1 has been encoded using QP values {22,27,32,37}. The DivX HEVC profile limits the keyframe interval. For this evaluation we have set the keyframe interval to 5 seconds for each encoding. For DivX265 and x265 configurations have been used that result in approx similar encoding speed and reasonalble quality (Balanced) For x264 preset slow has been used.

Encoding efficiency

The encoding efficiency can be derived from the rate-distortion plot. HM achieves the highest encoding efficiency, followed by DivX265 (balanced, main10), DivX265 (balanced) thereafter x265 (preset fast, main10), x265 (preset fast) and finally x264 (preset slow). The BD (Bjøntegaard Delta) rate has been calculated between DivX265 and x265 and is approx 5.6%. I.e. the DivX265 encoded stream is 5.6% smaller for the same quality.

Encoding speed

The next plot shows the relative speed of each encoder: DivX265 (balanced, main) is faster (~1.3x) than x265 (fast, main) at this preset while, as shown in the plot above, it is also 5.6% more efficient.

In summary, DivX265 can encode this sequence faster and more efficient than x265 at these settings. The encoding speed is approx 16 fps for balanced and faster than real-time, up to 40 fps, for the faster modes while the quality is better than x264 (AVC) for a given speed on this 4/8 core machine.

Encoding settings
Encoder version configuration parameters [tr]

DivX HEVC Community Encoder

DivX HEVC Team is excited to announce an updated version of our command line encoder for HEVC!

Download executable (Windows and Linux):

Using DivX HEVC Community Encoder

The DivX HEVC encoder is a command line tool that is capable of creating HEVC bitstreams.