Кодеки: вопросы и ответы

Проигрыватель Windows Media включает некоторые популярные кодеки, например MP3, Windows Media Audio и Windows Media Video. Однако он не содержит кодеки, необходимые для файлов Blu-ray, FLAC и FLV. Если что-то не работает в проигрывателе Windows Media, возможно, на вашем компьютере не установлены нужные кодеки. Самый простой способ устранить эту проблему — перейти в Интернет и найти кодек, который вам нужен.

Примечание: Не все проблемы с воспроизведением в проигрывателе Windows Media связаны с кодеками. Если проблема связана с кодеком, вы, вероятно, получите сообщение «Для воспроизведения этого файла необходим кодек» «В проигрывателе Windows Media произошла ошибка». В этом случае выполните действия, чтобы узнать больше о недостающих кодеках. Если оказалось, что это проблема не связана с кодеком, изучите раздел Устранение проблем со звуком в Windows Media Center для получения справки по проблемам со звуком и общим проблемам с воспроизведением.

Далее приведены ответы на некоторые распространенные вопросы о кодеках.

Кодек сжимает или распаковывает мультимедийные файлы, такие как песни или видео. Проигрыватель Windows Media и другие приложения используют кодеки для воспроизведения и создания файлов мультимедиа.

Кодек может состоять из двух частей: кодировщика, который сжимает файл мультимедиа (кодировка) и декодер, который распаковывает файл (декодирование). Некоторые кодеки включают в себя обе части, а другие кодеки включают только один из них.

В меню Справка проигрывателя Windows Media выберите пункт о проигрывателе Windows Media. Если меню » Справка » не отображается, выберите пункт упорядочить > Макет > Показать строку меню.

В диалоговом окне О программе нажмите ссылку Служба технической поддержки. В веб-браузере откроется страница, содержащая информацию о связанных двоичных файлах, кодеках, фильтрах, подключаемых модулях и службах, установленных на вашем компьютере. Эти сведения помогут вам устранить неполадки.

В настоящее время используются сотни звуковых и видеокодеков. Некоторые из них разработаны корпорацией Майкрософт, но большая часть кодеков создана сторонними компаниями, организациями или отдельными разработчиками. По умолчанию в операционной системе Windows и проигрывателе есть самые популярные кодеки, такие как Windows Media Audio, Windows Media Video и MP3.

Однако иногда требуется воспроизводить содержимое, которое было сжато, с помощью кодека, который Windows или проигрыватель не включает по умолчанию. Чаще всего необходимый кодек можно скачать в Интернете (платно или бесплатно) Кроме того, в некоторых случаях проигрыватель может автоматически использовать кодеки, установленные другими программами воспроизведения и создания цифрового мультимедиа на компьютере.

В этой ситуации вы, вероятно, пытаетесь воспроизвести, записать или синхронизировать файл, сжатый с помощью кодека, не содержащегося по умолчанию в Windows или проигрывателе.

Если вы знаете имя кодека или его идентификатор ( идентификатор FourCC для видеокодеков или идентификатор WaveFormat для аудиокодеков), выполните поиск в Интернете. В большинстве случаев скачать последнюю версию кодека можно на веб-сайте производителя кодека. Если вы не знаете название или идентификатор недостающего кодека, см. раздел Как определить, какой кодек использовался для сжатия файла и в каком формате файл?

Будьте внимательны при установке кодеков, которые вы найдете в Интернете, особенно в некоторых бесплатных пакетах кодеков, которые позволят вам включать кодеки из разнообразных компаний или организаций. Известны проблемы совместимости с некоторыми компонентами в этих пакетах кодеков, и это может привести к серьезным проблемам с воспроизведением в проигрывателе Windows Media и других проигрывателях, вызвать повреждение системы и заставить службу поддержки Майкрософт не диагностировать и устранять неполадки при воспроизведении.

Поэтому мы настоятельно не рекомендуем устанавливать эти пакеты кодеков, а если они установлены — советуем удалить их, если возникают проблемы при использовании проигрывателя. Устанавливайте только кодеки, фильтры и подключаемые модули из надежных источников, например с веб-сайта официального поставщика. Но даже в этом случае будьте осторожны: некоторые поставщики кодеков практически не предоставляют поддержку пользователям. Перед установкой любых цифровых мультимедийных компонентов создавайте точку восстановления системы. В случае необходимости она позволит вернуться к исходной конфигурации системы.

Совершенно точно определить, какой кодек использовался для сжатия файла, невозможно. Тем не менее доступны следующие способы:

Чтобы определить, какой кодек использовался для определенного файла, воспроизведите файл в проигрывателе, если это возможно. Во время воспроизведения файла щелкните его в библиотеке правой кнопкой мыши, а затем выберите пункт Свойства. На вкладке Файл просмотрите разделы Аудиокодек и Видеокодек.

Использование программы для идентификации кодеков, не являющихся Microsoft. Чтобы найти такое средство, выполните поиск «средством идентификации кодеков» в Интернете. Вы найдете несколько инструментов, а также полезные дополнительные сведения.

Вы можете указать формат файла, Взгляните на расширение имени файла (например, WMA, WMV, MP3 или AVI). Однако этот способ можно использовать не всегда. Многие программы создают файлы с настраиваемыми расширениями. Каждый может переименовать файл, не изменяя при этом формат файла. Например, файл с расширением. mpg или. DVR-MS обычно просто является сжатым файлом, который сжимается с помощью некоторых версий видеокодеков MPEG.

Декодер DVD — это другое имя для декодера MPEG-2. Содержимое дисков DVD-Video, как и файлов DVR-MS (записи телепередач Майкрософт) и некоторых файлов AVI, закодировано в формате MPEG-2. Чтобы воспроизвести эти элементы в проигрывателе, необходимо установить совместимый декодер DVD на компьютере.

Если на вашем компьютере есть DVD-дисковод, возможно, на нем уже установлен декодер DVD. Однако если вы получили сообщение об отсутствии совместимого декодера DVD, нажмите кнопку Веб-справка в диалоговом окне сообщения об ошибке, чтобы узнать, как можно получить этот декодер.

Возможно, на рабочем компьютере нет кодеков, которые установлены на домашнем компьютере.

Например, вы не сможете воспроизвести диск DVD-Video или файл DVR-MS на рабочем компьютере, если на нем не установлен совместимый DVD-декодер.

Обратите внимание, что системный администратор в вашей организации может использовать групповую политику, чтобы блокировать установку новых кодеков.

Кодеки можно писать для 32-разрядных или 64-разрядных операционных систем. Если вы используете 64-разрядную версию Windows, необходимо устанавливать 64-разрядные кодеки. Например, если вы установили 32-разрядный кодек в 64-разрядной операционной системе, проигрыватель может не суметь воспроизвести файлы, для которых требуется этот кодек.

Обратите внимание, что многие старые кодеки доступны только в 32-разрядных версиях. Если поставщик не указал версию кодека, вероятно, он 32-разрядный. Для получения дополнительных сведений обратитесь к поставщику кодека.

Вы можете попробовать приложение «Кино и ТВ» (Майкрософт) в качестве альтернативы проигрывателю Windows Media. Чтобы скачать его, введите Microsoft Store в поле поиска на панели задач, выполните поиск Кино и ТВ и прокрутите список результатов поиска вниз до раздела приложений.

Codecs: frequently asked questions

Windows Media Player includes some of the most popular codecs, like MP3, Windows Media Audio, and Windows Media Video. However, it doesn’t include the codecs required for Blu‑ray Disc files, FLAC files, or FLV files. If something isn’t working in Windows Media Player, you might not have the right codec on your PC. The easiest way to fix this problem is to go online and search for the codec you need.

Note: Not all Windows Media Player playback problems involve codecs. If your problem is codec-related, you’ll probably receive a message like «A codec is required to play this file» or «Windows Media Player encountered an error.» In this situation, follow the steps to learn more about the missing codecs. If it turns out that it’s not a codec issue, see Troubleshoot audio problems in Windows Media Center for help with audio problems and general playback issues.

Here are answers to some common questions about codecs.

A codec compresses or decompresses media files such as songs or videos. Windows Media Player and other apps use codecs to play and create media files.

A codec can consist of two parts: an encoder that compresses the media file (encoding) and a decoder that decompresses the file (decoding). Some codecs include both parts, and other codecs only include one of them.

On the Help menu in Windows Media Player, select About Windows Media Player. If you don’t see the Help menu, select Organize > Layout > Show menu bar.

In the About Windows Media Player dialog box, select Technical Support Information. Your web browser will open a page that includes a lot of detailed info about the related binary files, codecs, filters, plug-ins, and services installed on your PC. This info should help you troubleshoot problems.

There are hundreds of audio and video codecs in use today. Some have been created by Microsoft, but the vast majority of codecs were created by other companies, organizations, and individuals. By default, the Windows operating system and the Player include a number of the most popular codecs, such as Windows Media Audio, Windows Media Video, and MP3.

However, there might be times when you want to play content that was compressed by using a codec that Windows or the Player doesn’t include by default. In many cases, you can download the necessary codec from the web for free or for a fee. And, in some cases, the Player can automatically use the codecs installed by other digital media playback and creation programs on your computer.

In this situation, you’re probably trying to play, burn, or sync a file that was compressed by using a codec that Windows or the Player doesn’t include by default.

If you know the name of the codec or its ID (known as a FourCC identifierfor video codecs or a WaveFormat identifierfor audio codecs), try searching the internet for it. You can often go to a codec manufacturer’s website to download the most recent version of a codec. If you don’t know the missing codec’s name or ID, see How do I tell which codec was used to compress a file and what format a file is in?

Use caution when installing codecs that you find on the internet, particularly some of the free codec packs that claim to include codecs from a wide variety of companies or organizations. There are known compatibility issues with some of the components in these codec packs, and these can trigger serious playback problems in Windows Media Player and other players, cause system corruption, and make it difficult for Microsoft Support to diagnose and troubleshoot playback issues.

Therefore, we strongly discourage you from installing these codec packs and recommend that you remove them if you have installed them and are having problems with the Player. Install codecs, filters, and plug-ins only from trusted sources, such as the provider’s official website. Even then, use caution: some codec providers offer minimal customer support. Before installing any digital media components, set up a system restore point. This lets you return to your original system configuration, if necessary.

There isn’t a way to determine with absolute certainty the codec used to compress a file, but the following are your best options:

To determine what codec was used with a specific file, play the file in the Player, if possible. While the file is playing, right-click the file in the library, and then select Properties. On the File tab, look at the Audio codec and Video codec sections.

Use a non-Microsoft codec identification tool. To find one, search for «codec identification tool» on the web. You’ll find several tools as well as useful related info.

You might be able to tell the format of a file by looking at the file name extension (such as .wma, .wmv, .mp3, or .avi). However, there are limits to this approach. Many programs create files with custom file extensions. And it’s possible for anyone to rename a file without changing the file’s format. A file with an .mpg or .dvr-ms extension, for example, is usually just an AVI file that’s been compressed by using some version of an MPEG video codec.

A DVD decoder is another name for an MPEG-2 decoder. The content on DVD-Video discs is encoded in the MPEG-2 format, as is the content in DVR-MS files (Microsoft Recorded TV Shows) and some AVI files. To play these items in the Player, you need to have a compatible DVD decoder installed on your computer.

If your computer has a DVD drive, it probably already has a DVD decoder installed on it. However, if you receive an error message that indicates that you’re missing a compatible DVD decoder, select the Web Help button in the error message dialog box to determine how to obtain one.

This might happen if your computer at work doesn’t have the same codecs installed on it that your computer at home does.

For example, if you’re trying to play a DVD-Video disc or a DVR-MS file on your computer at work, and that computer doesn’t have a DVD decoder installed on it, you won’t be able to play that item until you install a compatible DVD decoder on your work computer.

Be aware that your system administrator at work might use Group Policy to prevent you from installing new codecs.

Codecs can be written for 32-bit or 64-bit operating systems. If you’re running a 64-bit version of Windows, you need to install 64-bit codecs. For example, if you install a 32-bit codec on a 64-bit operating system, the Player might not be able to play any files that require that codec.

Note that many older codecs are only available in 32-bit versions. If the codec provider does not specify whether its codec is 32-bit or 64-bit, the codec is likely 32-bit. For more information, contact the codec provider.

You might want to try the Microsoft Movies & TV app as an alternative to Windows Media Player. To get this, enter Microsoft Store in the search box on the taskbar, search for Movies & TV, and scroll down to the Apps section of the search results.

About the Windows Media Codecs

Windows Media Audio Codecs

Windows Media Audio 9

This codec samples audio at 44.1 or 48 kilohertz (kHz) using 16 bits, similar to the current CD standard, offering CD quality at data rates from 64 to 192 kilobits per second (Kbps). The resulting sound quality is 20 percent better than audio sampled with Windows Media Audio 8 at equivalent data rates.

The Windows Media Audio 9 codec (WMA 9) supports variable bit rate encoding (VBR), which enables even higher quality audio at smaller file sizes by automatically varying the encoding bit rate according to the complexity of the audio data. With VBR, the encoding bit rate increases to capture complex sections of data and then decreases to maximize the compression of the less complex sections, producing compact, high-quality compression.

WMA 9 is backward-compatible with previous Windows Media Audio-compatible decoders, which means that WMA 9 content can be played with previous versions of Windows Media Player or older consumer electronic devices that support Windows Media. As with all Windows Media 9 Series codecs, it supports the Windows Media digital rights management platform, which is used to securely package and distribute copy-protected digital media.

Windows Media Audio 10 Professional

Windows Media Audio 10 Professional (WMA 10 Pro) is the most flexible Windows Media audio codec available – supporting profiles that include everything from full-resolution 24-bit/96 kHz audio in stereo, 5.1 channel, or even 7.1 channel surround sound, to highly efficient mobile capabilities at 24 Kbps to 96 Kbps for stereo, and 128 Kbps to 256 Kbps for 5.1-channel sound. WMA 10 Pro offers incredible quality for consumers using high-fidelity hardware and 5.1 channel surround sound-equipped computers — and for consumers playing audio content on their mobile devices. WMA 10 Pro supports streaming, progressive download, or download-and-play delivery at 128 to 768 Kbps.

When using 5.1 surround sound audio compressed at 384 Kbps with WMA 10 Pro, most listeners cannot discern any differences between the compressed music and the original pulse code modulation (PCM) files. WMA Pro also offers dynamic range control using the maximum and average audio amplitudes that are calculated during the encoding process. Using the Quiet Mode feature in Windows Media Player 9 and later, users can hear either the full dynamic range, a medium difference range up to 12 decibels (dB) above the average, or a little difference range up to 6 dB above the average.

If a user tries to play back a file that was encoded using the 5.1 channel, 24-bit, 96 kHz sampling capabilities, but does not have a system or sound card that supports multi-channel or high-resolution sound, multiple channels are combined into stereo audio (for example, 16-bit, two channel audio), ensuring that users get the best playback experience their systems can provide.

The following table compares WMA Pro to competing compression technology.

Audio Data	Industry Compression*	Windows Media*	Compression Savings
2 ch x 48 kHz x 16 bits	Dolby Digital 2.0 at 220 Kbps	WMA 10 Pro at 128 Kbps	1.7:1
6 ch x 48 kHz x 20 bits	Dolby Digital 5.1 at 384 Kbps	WMA 10 Pro at 192–256 Kbps	1.5–2:1
6 ch x 48 kHz x 24 bits	DTS 5.1 at 1,536 Kbps	WMA 10 Pro at 768 Kbps	2:1

Windows Media Audio 9 Lossless

The audio quality of content that is compressed using this codec is the best of all Windows Media Audio codecs. It creates a bit-for-bit duplicate of the original audio file so that no data is lost, which makes it ideal for archiving content masters.

Depending on the complexity of the original, content will be compressed at a 2:1 or 3:1 ratio. Although this is lower than the ratio achieved with other Windows Media Audio 9 Series codecs, it provides the same benefits of compression while leaving the data intact.

Like Windows Media Audio 9 Professional, the Windows Media Audio 9 Lossless codec also offers dynamic range control using the maximum and average audio amplitudes that are calculated during the encoding process. Using the Quiet Mode feature in Windows Media Player 9 and later, users can hear the full dynamic range, a medium difference range up to 12 dB above the average, or a little difference range up to 6 dB above the average.

Windows Media Audio 9 Voice

This low-bit-rate codec is primarily targeted for speech content, but performs very well with mixed-mode content that includes both voice and music. In voice mode, the codec takes advantage of the relatively less complicated and narrower frequency range of the human voice to maximize compression. In music mode, the codec operates like the standard Windows Media Audio 9 codec. Encoded content can be configured to switch between voice and music modes automatically.

The Windows Media Audio 9 Voice codec offers superior quality for low-bit-rate streaming scenarios (less than 20 Kbps), such as radio broadcasts, advertising, e-books, podcasts, and voiceovers. The voice codec can also compress content to as low as 4 Kbps at 8 kHz.

Compatibility

The following table outlines what your audience will experience when playing Windows Media Audio 9 Series content on earlier Microsoft Windows operating systems than Windows XP or with earlier versions of Windows Media Player. This table also lists the compatibility for Apple Mac OS X and Windows CE–based platforms.

Codec	Feature	Player backward compatibility
Windows Media Audio 9	Constant-bit rate (CBR) encoding	Windows Media Player 6.4 or later on non-portable devices (using transcoding as needed) Windows Media Player 9 for Mac OS X Windows Media Player 9 Series and Windows Media Player 9.1 for Pocket PC* Windows Media Player 9 Series and Windows Media Player 9.1 for Smartphone*
Variable-bit-rate (VBR) encoding	Windows Media Player 7 or later on all devices that support the Player (using transcoding as needed)
Windows Media Audio 9 Professional	General	Windows Media Player 7 or later Windows Media Player 9 for Mac OS X
Discrete channel playback (for instance, 5.1)	Requires Windows Media Player 9 Series (or SDK) or later, Windows XP, and a multichannel audio card.
High-resolution audio (24-bit, 96 kHz)	Requires Windows Media Player 9 Series (or SDK) or later, Windows XP, and a high-resolution audio card.
Dynamic range control	Requires Windows Media Player 9 Series (or SDK) or later and Windows XP.
Windows Media Audio 9 Lossless	General	Windows Media Player 7 or later Windows Media Player 9 for Mac OS X
Discrete channel playback (for instance, 5.1)	Requires Windows Media Player 9 Series (or SDK) or later, Windows XP, and a multichannel audio card.
Windows Media Audio 9 Voice	General	Windows Media Player 6.4 or later Windows Media Player 9 for Mac OS X Windows Media Player 9 Series and Windows Media Player 9.1 for Pocket PC* Windows Media Player 9 Series and Windows Media Player 9.1 for Smartphone*

* All versions of Windows Media Player for Pocket PC and Smartphone are shipped as part of the Microsoft Windows Mobile operating system. Windows Media Player for Pocket PC and Windows Media Player for Smartphone are not available for download from Microsoft.

Windows Media Video 9 Series Codecs

In 2006, the Society of Motion Picture and Television Engineers (SMPTE) formally published the Final Specification for SMPTE 421M, also known as VC-1. Formal standardization of VC-1 represents the culmination of years of technical scrutiny by over 75 companies, leading to a codec that is well-documented, extremely stable, easily licensable, and accepted by the industry. VC-1 supports three profiles: Simple, Main, and Advanced. The Simple and Main profiles have been complete for several years, and existing implementations such as WMV 9 have long supported the creation and playback of content using these profiles, as well as an early implementation of the Advanced profile. The completion of the Advanced profile and consequent standardization of all profiles in VC-1 represents the final step in a comprehensive specification that delivers high definition content—either interlaced or progressive—across any medium and to any capable device.

Windows Media Video 9

Windows Media Video 9 is the Microsoft implementation of the VC-1 SMPTE standard. It supports Simple, Main, and Advanced profiles.

Simple and Main Profiles

The Windows Media Video 9 Simple and Main profiles fully conform to the SMPTE VC-1 standard and provide high-quality video for streaming and downloading. These profiles support a wide range of bit rates, from high-definition content at one-half to one-third the bit rate of MPEG-2, to low-bit-rate Internet video delivered over a dial-up modem. This codec also supports professional-quality downloadable video with two-pass and variable bit rate (VBR) encoding. Windows Media Video 9 is already supported by a wide variety of players and devices.

Advanced Profile

The Windows Media Video 9 Advanced profile fully conforms to the SMPTE VC-1 standard, supports interlaced content, and is transport-independent. Content creators can use this profile to deliver either progressive or interlaced content at data rates as low as one-third that of the MPEG-2 codec—with the same quality as MPEG-2.

In the past, interlaced video content was always de-interlaced before encoding with the Windows Media Video codec. Now, encoding applications such as Windows Media 9 Series, and third-party encoding solutions can support compression of interlaced content without first converting it to progressive content. Maintaining interlacing in an encoded file is important if the content is ever rendered on an interlaced display, such as a television.

Transport independence also enables the delivery of Windows Media Video 9 Advanced Profile over systems that are not Windows Media-based, such as standards-based broadcast infrastructures (through native MPEG-2 transport streams), wireless infrastructures (using real-time transfer protocol [RTP]), or even DVDs.

The following table compares Windows Media Video 9 Advanced Profile to competing compression technology.

Video Data	Industry Compression*	Windows Media*	Compression Savings
480/24p 720×480 pixels/frame x 8 bits per channel x 24 fps	MPEG-2 at 4–6 Mbps	Windows Media Video 9 Advanced Profile at 1.3–2 Mbps	3:1
480/30i 720×480 pixels/frame x 8 bits per channel x 30 fps	MPEG-2 at 6–8 Mbps	Windows Media Video 9 Advanced Profile at 2–4 Mbps	2–3:1
720/24p 1280×720 pixels/frame x 8 bits per channel x 24 fps	MPEG-2 at 19 Mbps	Windows Media Video 9 Advanced Profile at 5–8 Mbps	2.4–3.8:1

Windows Media Video 9 Screen

The Windows Media Video 9 Screen codec is optimized for compressing sequential screen shots and highly static video that is captured from the computer display, which makes it ideal for delivering demos or demonstrating computer use for training. The codec takes advantage of the typical image simplicity and relative lack of motion to achieve a very high compression ratio.

During the encoding process, the codec automatically switches between lossy and lossless encoding modes, depending on the complexity of the video data. For complex data, the lossless mode preserves an exact copy of the data. For less complex data, the lossy mode discards some data to achieve a higher compression ratio. By automatically switching between these two modes, the codec maintains video quality while maximizing compression.

Overall, the Windows Media Video 9 Screen codec delivers better handling of bitmap images and screen motion, even on relatively modest CPUs. It is also up to 100 times more efficient than the commonly-used run length encoding.

Windows Media Video 9 Image Version 2

The Windows Media Video 9 Image Version 2 codec is different from the other video codecs. Instead of processing uncompressed video, it transforms still images into video by using pan, zoom, and cross-fade transitions between clips to create an unlimited number of effects.

The results can then be delivered at data rates as low as 20 kilobits per second (Kbps). These files are compressed using either constant bit rate (CBR) or one-pass variable bit rate (VBR) modes.

The Windows Media Video 9 Image Version 2 codec is not compatible with the Windows Media Video 9 Image codec.

Windows Media Video 9 VCM

The Video Compression Manager (VCM) version of the Windows Media Video 9 Series codec enables earlier versions of encoding and editing applications to support the Windows Media Video 9 Series codec in file containers such as Audio Video Interleaved (AVI). This codec package also allows Windows Media Video (WMV) files based on Windows Media Format 9 Series to be played in Windows Media Player 6.4, in both ASF and AVI file containers.

Compatibility

The following table outlines what your audience will experience when playing Windows Media Video 9 Series content on earlier Microsoft Windows operating systems or with earlier versions of Windows Media Player. This table also lists the compatibility for Apple Mac OS X and Windows CE–based platforms.

Codec	Feature	Player backward compatibility
Windows Media Video 9	General	Windows Media Player 6.4 or later Windows Media Player 9 for Mac OS X Windows Media Player 9 Series and Windows Media Player 9.1 for Pocket PC* Windows Media Player 9 Series and Windows Media Player 9.1 for Smartphone*
Frame Interpolation	Requires Windows Media Player 9 Series (or Software Development Kit) or later and Windows XP.
Windows Media Video 9 Advanced Profile	General	Windows Media Player 7 or later
Windows Media Video 9 Screen	General	Windows Media Player 7 or later
Windows Media Video 9 Image Version 2	General	Windows Media Player 7 or later

*All versions of Windows Media Player for Pocket PC and Smartphone are shipped as part of the Microsoft Windows Mobile operating system. Windows Media Player for Pocket PC and Windows Media Player for Smartphone are not available for download from Microsoft.