After clicking on the screwdriver icon next to the LAV Video Decoder, you'll be presented with the following settings screen: Video Settings Hardware Acceleration Hardware Acceleration is used to let the GPU decode the video to leave the CPU free to do other things. The LAV Video Decoder supports several hardware decoders: • None: The video will be decoded by CPU, possibly burden it to a level that the result is stuttering video. • NVIDIA CUVID: Nvidia's CUDA based decoder. Video frames are decoded with the same hardware as with DXVA on GPU, but the video frames are required to be copied back to system RAM. • Intel QuickSync: Similar to CUVID, but for Intel's GPU:s. • DXVA2 (copy-back): Can be used by any hardware that supports DXVA2 (Intel might have some issues with VC1 video). Uses more GPU / memory bandwidth since every video texture is copied back to main RAM after decoding (hence the copy-back in name). • DXVA2 (native): Can be used by any hardware that supports DXVA2 (Intel might have some issues with VC1 video). Has issues with Blu-ray support in MediaPortal 1 (dropped frames on clip boundaries as DXVA requires video decoder to flush few frames). LAV Video Configuration Video Settings 1
After clicking on the screwdriver icon next to the LAV Video
Decoder, you'll be presented with thefollowing settings screen:
Video Settings
Hardware AccelerationHardware Acceleration is used to let the
GPU decode the video to leave the CPU free to do other things.
TheLAV Video Decoder supports several hardware decoders:
None: The video will be decoded by CPU, possibly burden it to a
level that the result is stutteringvideo.
NVIDIA CUVID: Nvidia's CUDA based decoder. Video frames are
decoded with the same hardwareas with DXVA on GPU, but the video
frames are required to be copied back to system RAM.
Intel QuickSync: Similar to CUVID, but for Intel's GPU:s. DXVA2
(copy-back): Can be used by any hardware that supports DXVA2 (Intel
might have some
issues with VC1 video). Uses more GPU / memory bandwidth since
every video texture is copiedback to main RAM after decoding (hence
the copy-back in name).
DXVA2 (native): Can be used by any hardware that supports DXVA2
(Intel might have some issueswith VC1 video). Has issues with
Blu-ray support in MediaPortal 1 (dropped frames on clipboundaries
as DXVA requires video decoder to flush few frames).
LAV Video Configuration
Video Settings 1
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DXVA2 (native) versus DXVA2 (copy-back)DXVA implementations come
in two variants: native and copy-back. Almost all implementations
are of thenative type. The LAV video decoder that is included in
the pack offers both variants. The internal DXVAdecoders in MPC-HC
are native implementations, and ffdshow also offers a native
implementation.
With the native type, the decoded video stays in GPU memory
until it has been displayed. This brings somelimitations with
regard to playback. The DXVA decoder must be connected directly to
the video renderer.There can be no processing filter in between.
The video renderer must also support DXVA, which give youa bit less
freedom of choice in renderers. The reason for keeping the decoded
video inside GPU memory isefficiency. Many graphics chips haven't
been optimized for copying data from GPU memory back to CPUmemory.
They are too slow for smooth playback. They can only copy data fast
in the other direction. Thisis the case for old AMD/ATI and old
Intel chips.
DXVA implementations of the copy-back type will, as the name
already suggests, copy the decoded videofrom GPU memory back to CPU
memory. Such implementations don't have the limitations
mentionedabove and act similar to a normal software decoder. DXVA
copy-back only works properly if the GPU cancopy the data fast
enough. Otherwise it will give stuttering video playback. GPU:s
that should be fastenough are:
NVIDIA: All models of the past few years Intel: Intel HD
Graphics 2000 and newer AMD/ATI: Radeon HD 6xxx and newer
LAV Video Configuration
Video Settings 2
Formats
LAV Video Configuration
Formats 3
Video SettingsHardware AccelerationDXVA2 (native) versus DXVA2
(copy-back)
