Cedocida DV Codec
Introduction:
Cedocida is an open source Video for Windows (VfW) DV-Type2-Codec.
Features:
- supported formats for in- and output: RGB, YUY2, YV12 (DV /
MPEG2-I / MPEG2-P)
- direct YV12 input/output without color shift, interpolation or conversion when using "YV12 (DV)"
option
- optional forcing of selected input and output format
- settings for picture quality and compression methods
Screenshot of configure dialog box:
Description of selected settings:
- force input format
If enabled, the encoder/decoder only accepts the selected
format for input/output. This could result in an error message
if the used application does not support this format.
When disabled, the selected format is only the primary suggestion
for the application that uses this codec.
- *YV12 chroma sampling
The YV12 format is a planar YUV color format with 4:2:0 subsampling.
The position of the chroma samples differs with the compression
standard using it.
Using the first option (DV), the pixel data is directly feed to
or from the the compression algorithm without color shift, interpolation
or conversion.
For (MPEG 2 non interlaced) and (MPEG 2 non interlaced) the data
is preprocessed or postprocessed in order to match the given color
sampling positions.
Some remarks on "YV12 (DV)" input/output option in combination
with NTSC video:
Because NTSC DV uses 4:1:1 subsampling type, you will see weird
color when viewed with a normal YV12 program which assumes 4:2:0.
This is no bug. If you need YV12 format for producing DVD content,
use the option "YV12 (MPEG 2 *)".
- DCT 2-4-8 mode selection
In principle: if absolute pixel-value-difference between pixel
(x,y) and pixel (x,y+1) is greater then <threshold> a counter
is increased. If this counter value (after analyzing 6x8 pixel
differences) is greater then <counts> the DV-specific 2-4-8
Discrete Cosine Transform is used, otherwise the normal 8-8 DCT.
- classification
Please have a look at the DV-Standard (IEC 61834-2). This affects
image quality.
Installation:
- Compile the sourcecode with e.g. Microsoft Visual C++ and NASM
(has to be in the search path of executables). If there are no errors,
you will find all files for installation in the folder "bin".
- Install as regular DV-Codec (VfW). Your actual DV-Codec will
be replaced by this one.
==> in .\bin right click on "cedocida.inf" and
select install
Download sourcecode (ready to compile with VC++ 2005 (Express) and NASM):
News:
2007-Aug-07:
- Released Cedocida 0.2.0
- fixed multithreading issues
- ported to Visual Studio 2005 (Express)
- fixed bugs in inf file and added install/uninstall support for x64 systems
- fixed other minor bugs
- etc.
2007-Jan-02:
- Released Cedocida 0.1.7
- Fixed: bug in encoding/decoding right border of interlaced ntsc video
- Fixed: bug in encoding if frame activity is too high
- Fixed: bug in DIF-Header, wrong position of video-packets
- Fixed: minor bugs in GUI
2005-May-23:
- New: encoding and decoding of NTSC video
- Fixed: bug concerning U-V-color-swap of YV12 encoding/decoding
2005-May-12:
- Released Cedocida 0.1.5
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