1. 前言/基础
在这份指南中，你将能学习到如何将模拟视频捕捉到电脑，如何进行后期处理以获得满意的质量，我们也会给出一些关于视频编码和制作的连接。本指南中的视频源指的是PAL或NTSC系统，处理后将获得可在电脑上播放的DivX3/DivX5/FFVFW/XviD文件，或是用在独立的DVD播放机上的DVD/SVCD/CVD/VCD。
我们将采用VirtualDub(基于Vfw)和VirtualVCR(基于WDM)这两种软件进行捕捉.它们的效果好于随你的视频捕捉卡所赠送的mpeg2捕捉软件。我们将把捕捉和存储两种任务完全分离。也就是说，首先把“原材料”(包括后期将被去除的广告和其它一些垃圾)通过基本无损的压缩存到硬盘上。然后再进行处理和转换到最终格式的任务。我们将给出两种不同的捕捉方法。你可以自由选择其一，适合你的就是最好的。不过，在选择过程中我们也会提供一些帮助。
捕捉到的视频有两种不同的后期处理方法：Virtualdub相对比较简单而AviSynth则比较复杂。一开始AviSynth可能会让你有恐惧感，但是你应该关注一下AviSynth的ASAP部分并学习这一简单脚本语言，它能加快你的编码过程且效果极佳。我们将会针对VirtualDub和AviSynth讨论如下几个问题：
- 基本的后期处理：deinterlacing, Resizing和color correction
- 如何去除logo
- 如何去除chroma artefacts (chroma noise, color crosstalk, chroma phase problems,等等)
- 如何去除clicks和scratches
本指南主要是关于如何进行捕捉，后期处理而非编码及制作。在这方面已经有非常多优秀的教程。因此，本指南的编码/制作/刻录部分包括了相关指南的连接（Doom9上有提供）。我们将把重点放在免费的工具上。
本文的原作者BaronVlad有如下注释：“这篇指南仅是一篇指引性文章而决不是达到目的的唯一的办法。它既不包括所有可行的办法，也不涵盖这个主题下的所有信息。仅是提供一种方法，并附有前人所发现的一些关于捕捉的有用技巧。当开始对捕捉进行研究时（就在不久之前），我根本找不到一篇详尽的指南，但这有可能是因为我不知道到哪去找。于是我有了避免使其它人进行重复劳动的想法。”
在开始进行视频捕捉之前，你得做出两个重要的决定：想得到什么样的最终格式和捕捉所用到的编码器。
1.1 最终格式
应该选择什么格式呢？这取决于你倾向于用什么来回放视频。假如你只想在电脑上播放，我们建议你采用DivX3（Nandub）或是FFVFW。你也可以使用DivX5/Xvid
but they don't handle noise very well ,但它们处理噪点的能力不佳（至少在写这篇文章时），虽然可以用去噪器减轻影响。这些解码器能够使你用相对少量的空间（cd或是硬盘）来储存高品质的视频。现在，有些独立播放器也能够回放DivX文件。但大部分的人还在使用只能回放mpeg1 （VCD） 和mpeg2 （DVD, SVCD或CVD）的标准DVD播放器。甚至有些还不支持SVCD,所以在开始之前你有可能要再核对一下。
1.2 用于捕捉的编码器
基本上，你的捕捉应该是(几乎)无损的。因此我们将介绍Huffyuv和PicVideo MJPEG这两种编码器。HUffyuv质量最高，但在选择高捕捉尺寸的同时会牺牲较大的空间（一般来说一小时的全尺寸视频需要20-40G）。这个编码器是免费的，这点很好。PicVideo MJPEG是第二种选择。PicVideo相当不错因为它消耗资源较少。此外，MJPEG编码解码器还有Morgan和Leadtech两种版本。这两种版本有个缺点，只有在高端系统上才能展现其质量上的优势。PicVideo和Huffyuv之间的区别是在MJPEG编码器中你能够调整编码的质量。使用最高设置（20）的情况下，生成的文件与Huffyuv一样大，但如果你用18或是19的话，在不明显损伤视频质量的同时文件尺寸会大辐下降。
稍微提醒一下， MJPEG编码器生成的图像不如Huffyuv锐利，这可能与个人所需不符。另外，此编码器不是免费的;你必须得花钱注册它以使生成的图象上没有水印（虽然我们会在后续过程中处理它）。
在处理这么大的文件时，处理器和硬盘的工作负荷相当大。因此在选择编码器的同时，你还需要考虑你的硬件条件。你所需要的是一个快速的处理器和一个快速的硬盘。但是由于文件尺寸很大程度上取决于所选择的解析度，你还是需要再考虑一下你的最终选择。
下载链接：
- Huffyuv: Huffyuv v2.1.1 CCE SP-Patch v0.2.5 (make sure you use at least the v0.2.2 patch)
1. Preface / Basics
For starters, since it has to be said: it is prohibited by international law to use this guide to make illegal copies of copyright protected audio and video material.
In this guide you will be able to learn how you can capture analogue video material to your computer, what kind of post processing should be done to get good quality and some links are given for the encoding and authoring of your processed video. The source will be a PAL or a NTSC system and you should end up with a DivX3/DivX5/FFVFW/XviD file for playback on a PC, or a DVD/SVCD/CVD/VCD for playback in a standalone DVD player.
The programs used for capturing are VirtualDub (VfW based) and VirtualVCR (WDM based). They allow you to achieve better results than with the mpeg2 capture software provided with your capture card. We separated the tasks of capturing and storing the video. This means that you first save the material (including commercials and all the other junk you'll later want to get rid of) in almost lossless compression to your hard drive. Afterwards you deal with the task of processing and converting it to its final format. We are going to describe two possibilities for capturing. The choice is solely up to you, since "best" is what works best for you. Nevertheless, some support for your decision making will be provided.
Postprocessing the captured video will be explained in two different ways: an "easy" way using Virtualdub and a more advanced way using AviSynth. In the beginning AviSynth might scare you, but you should take a look into the AviSynth part ASAP to learn this simple scripting language, because it will speed up the encoding process and can give you very good results. For VirtualDub and AviSynth, the following subjects are discussed:
* the basic postprocessing like: deinterlacing, resizing and color correction
* removal of logos
* removal of chroma artefacts (chroma noise, color crosstalk, chroma phase problems, etc.)
* removal of clicks and scratches
This guide is mainly about capturing, postprocessing and not about encoding or authoring. There exists already plenty of good guides which explain this process to you. Therefore, the encoding/authoring/burning part consists of links to the relevant guides (which can be found on Doom9's site). The emphasis will be on free tools.
The original author BaronVlad comments "This guide is merely a guideline and definitely not the only way to achieve the desired results. Nor is it by any means complete, nor does it contain all information existing on this topic. It is only one approach, and provides some tips people have found useful for capturing to their liking. When I started putting my time into this topic (which wasn't very long ago) I wasn't able to find a complete guide, probably because I didn't know where to look. I want to save everybody else having to "reinvent the wheel"."
There are two important decisions to make before you start capturing: the desired final format, and your capture codec.
1.1 Desired Final Format
What format should you choose? This depends especially on what you intend to play back the video with. If you just want to play it on your computer, we suggest to go with DivX3 (Nandub) or FFVFW. You could also use DivX5/XviD, but they don't handle noise very well (at the moment of writing this page). Although this can be reduced if you use good denoisers. These codecs will enable you to save the video in very high quality in a relatively small amount of space (CD or hard drive). Nowadays, some stand-alone players are also capable of playing back DivX files. Most people however still own standard DVD players which can play back mpeg1 (VCD) and mpeg2 (DVD, SVCD or CVD). Some players do not even support SVCD, so you may want to check this before starting.
1.2 Capture codec
Basically, your capture should be (almost) lossless. Therefore two codecs will be described, the Huffyuv codec and the PicVideo MJPEG Codec. Huffyuv produces the best quality, but when choosing a higher capture size you need relatively large amounts of disk space (typically 20-40 gigabyte per hour of full size video). On the positive side, the codec is free. The second choice is the PicVideo MJPEG codec. The PicVideo version is good because it consumes rather few resources. Other MJPEG codecs are provided by Morgan and Leadtech. The problem with their versions is that you can use the quality advantages only with a high end system. The differences between PicVideo and Huffyuv are that you can adjust the encoding quality in the MJPEG codec. Using the highest setting (20), the file size can get as large as the Huffyuv file, but if you use 18 or 19 the file size decreases significantly without harming the video quality significantly.
A small warning, the MJPEG codec produces a picture that is a little less sharp than Huffyuv, which may not fit everybody's needs. In addition, the codec is not free; you have to register and pay a fee to avoid watermarks being put onto the video (we are going to handle them later on though).
When handling such large files, both the processor and your hard disk will incur a significant work load. Therefore when choosing the codec, you should also consider your hardware. You'll need a fast processor and a fast hard disk. But since the file size also depends very much on the resolution you're choosing, you should also consider your final choice.
