买家必备视频工具指南
You can't effectively perform as a compressionist without tools that reveal critical details about your encoded files, whether they are basics like codec, resolution, and data rate or are deep-level elements like group-of-pictures (GOP) structure and quality levels. This guide identifies the functions you need as well as the tools that can supply them, how much they cost, and where to get them.
本指南是全面的，但不是详尽的. 如果你想了解你应该为自己购买的工具, please use it as a starting point. 如果你销售的工具，你认为我们应该考虑，但没有, 请在下面的评论中告诉我们.
Free Tools
如果一个工具是免费的并且服务于一个有用的目的, 没有理由不在每台支持它的计算机上安装它. 这个类别中有两个:MediaInfo和Bitrate Viewer.
MEDIAINFO
What: 一种文件分析工具，用于识别 密钥编码配置细节如 audio/video codec, profile, bitrate, resolution, frame rate, audio channels, and sampling rate. The tool is free and available 适用于Windows, Mac, Ubuntu, iOS, Android， and many other operating systems.
Where: bit.ly/SM_MI
How much: Free; donations accepted
Fun fact: Once installed, you can hover
你的指针在任何文件在Windows百家乐软件管理器和查看基本的音频/视频
codec and encoding info.
See it in action: bit.ly/SM_MI_BV (YouTube video)
Verdict: This tool should be installed on 你办公室和家里的每一台电脑.
BITRATE VIEWER
What: A Windows-only tool that shows the per-frame or per-GOP size and average data rate for MPEG-2 and H.264编码文件(但不适用HEVC, AV1或更高版本的编解码器). It also displays file resolution; frame rate; and minimum, maximum, and average bitrate.
Where: bit.ly/brv_dl
How much: Free
Fun fact: You can zoom into the display with your mouse wheel to better view frame details.
See it in action:
bit.ly/SM_MI_BV (YouTube video)
Verdict: 操作系统和文件兼容性的限制令人沮丧，但是 你应该在每台Windows电脑上安装这个程序
in your office.
File-Analysis Tools
These tools allow you to analyse files that Bitrate Viewer doesn't and provide much more detail. But they're not free.
TELESTREAM SWITCH
What: 一个可以播放视频的Windows/Mac工具, 显示文件细节，如GOP结构和数据速率, 检查音量和字幕细节. Telestream提供三个版本(9美元).99, $199, and $499), and you'll need the $499 version to get the GOP view shown in Figure 3 and the data-rate view. 它可以检查大量的容器和编解码器，包括HEVC，但不包括AV1.
Where: bit.ly/teleswitch
How much: $499
Fun fact: It can load two files at once and allow you to toggle between them or show them side by side. Figure 3 shows the file encoded with the Medium x264 preset on the left and Veryfast on the right. 你可以在超级名模的脸上看到拖拽条手柄.
Verdict: I wish Telestream offered a version with just the file visualisation tools and not the fancy production capabilities (captions, audio volume, export), 哪些百家乐软件app最新版下载不使用. Still, it's the cheapest option for viewing GOP structure and data rate of files that Bitrate Viewer doesn't support.
ZOND 265
What: 一个深度文件分析工具，运行在Windows, Mac和Linux上. 有两个版本:基本版, 它支持HEVC，但不提供命令行(391美元), and Full Edition, which supports HEVC, AVC, AV1, 和MPEG-2文件通过GUI或命令行($1,390). Some functions benefit all users, including the ability to display both data-rate and GOP views and compute Video Multimethod Assessment Fusion (VMAF), 多尺度结构相似性(MS SSIM), 峰值信噪比(PSNR)得分. 其他的主要用于编解码器开发人员和编码供应商, such as the ability to validate HEVC files and visualise details like the HRD buffer and prediction partitions .
Where: bit.ly/SM_Zond
How much: Essential Edition, $391; Full Edition, $1,390
Fun fact: Zond 265 can provide frame details like the percentage of compression achieved via inter- and intra-frame encoding and can identify reference frames used for each frame encode and the percentage of reference pictures each provided.
Verdict: The Telestream Switch is better if all you want are bitrate graphs and GOP structure views. 但如果你正在寻找深度文件分析，Zond 265是更好的选择.
ELECARD VIDEO QUALITY ESTIMATOR
What: This resource sits between the analysis tools previously mentioned and the metrics tools that will follow, providing deep file analysis, GOP and data-rate views, 以及计算PSNR等指标的能力, Media Source Extension (MSE), SSIM, and VMAF. It is compatible with H.264, HEVC, VP9, and AV1. It offers excellent file-visualisation tools but is clunky; e.g., in the version we tested, we had to convert the source file to YUV before comparing it to the compressed files. Also, the programme doesn't support drag and drop, which is frustrating during high-volume usage. The command-line option works via an XML configuration file rather than a simpler and more traditional command-line syntax. 它可以在Windows、Mac、Ubuntu、CentOS和Fedora上运行.
Where: bit.ly/SM_VQE
How much: Not cited on the website. When we reviewed it, the GUI mode cost $850, and the command-line version cost an additional $400.
Our review: bit.ly/SM_VQ_rev
Verdict: 如果您需要这两个文件，这是一个很好的选择 分析和参数，但首先下载并测试试用版.
HONORABLE MENTION
Beamr View: This free tool allows side-by-side comparisons of two files to assist in GoldenEye testing and shows the bitrate, resolution, frame rate, frame type, and PSNR value for each frame. Beamr View由Beamr提供，以协助评估公司的产品, but you have to request a trial version that expires after either 3 or 6 months. 如果您想继续使用波束视图, 可按付费计划获得多座牌照(bit.ly/SM_VU).
Vooya: Like Beamr View, Vooya enables side-by-side comparisons but provides less data per frame. It's primarily useful for projects that involve YUV or other raw formats that most players won't load but Vooya can. Mac和Windows系统的Vooya售价为20美元，但Linux系统是免费的。bit.ly/SM_Vooya).
Video Quality Metric-Related Tools
The primary function for the following tools is to compute and visualise video quality metric scores.
莫斯科国立大学视频质量测量工具(msu vqmt)
What: 该工具计算一系列视频质量指标, including VMAF, PSNR, SSIM, MS SSIM, and many others. It can compare two files in the GUI simultaneously so you can compare codecs or encoding techniques. It displays the comparative metric score over the duration of the file so you can identify quality drops and where the compared files differ and then view the frames themselves. 命令行操作简单灵活，可以输出 in JSON and CSV. 度量分数现在包括谐波平均值, lowest-quality frame, highest-quality frame, standard deviation, and variance, 这些都为算术平均值添加了上下文. GUI runs only on Windows; the command-line version runs on Linux DEB
and Linux RPM.
Where: bit.ly/SM_VQMT
How much: $299–$999, depending on volume
Fun fact: 莫斯科国立大学是最全面的HEVC和H的作者.264 codec comparisons, for which VQMT was developed, and also created Subjectify.Us是一个众包图像和视频主观评价的网站.
See it in action: bit.ly/MSU_V12 (YouTube video)
Verdict: MSU VQMT提供了易用性的完美融合, performance, 以及有助于对编解码器和编码参数做出明智决策的数据.
SSIMPLUS VOD MONITOR
What: A browser-based tool for computing SSIMPLUS (SSIMWAVE's video quality metric) and displaying the results graphically with the ability to view the actual frames at any location in the file. Another view produces rate-distortion curves and BD-Rate computations to visualise and quantify the performance differences between codecs. 它可以同时比较多个文件, 因此，在比较两个以上的编码选择时，它非常有用. 它支持广泛的编解码器，包括H.264, HEVC, VP8, VP9和AVI，并且还支持高动态范围(HDR). SSIMPLUS is one of the few metrics that can compute scores from files of different frame rates, 就像从1080p60源编码的720p30文件.
该软件运行在CentOS(任何受支持的文件系统)上。, VirtualBox, 它支持AWS和谷歌云平台的云计算功能.
Where: bit.ly/SM_VODMon
How much: Not disclosed
Fun fact: SSIMPLUS是由周旺领导的团队开发的, SSIM算法的开发者, 谁获得了2015年的工程艾美奖.
Verdict: 获得SSIMPLUS评级的唯一途径. 它的操作速度非常快，而且GUI增加了很多价值.
HONORABLE MENTION
FFmpeg: A free open source command-line utility that can compute PSNR, SSIM, and VMAF. 没有简单的方法来可视化相关的框架, however, 在比较编解码器或评估编码技术时，哪个是关键的. This makes FFmpeg good for integrating into a production workflow but not optimal for research and analysis.
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