Production of high-quality MP3 Raiders Preface Author: Blue Ying [2004-05-28] MP3 quality depends on the quality and method of making the sound source, whether it is extracting audio data from the CD album, VCD movies converted to MP3 or other media, and Or simply convert other audio files to MP3 files, you need to master the right way to make high quality MP3 files.
MP3 is the current most popular audio compressed format, but disputes around MP3 quality have never been broken, in APE, FLAC non-destructive compression format and MPC, OGG these highly competitive damaged compression formats, MP3 Quality is more questionable, and even a lot of music enthusiasts immediately immediately learns to be poor. As a lossless compression format, the MP3 does not indeed comparing with high quality sound sources such as CD records, but evaluates a good or bad in the format of audio compression, requires all aspects of compression ratio, compression speed, and compressed sound quality. Comparison, and must be compared to the quality of compression at low bit rates and high bit rates, respectively, to achieve results that have truly reference value. The size of the MP3 file is undoubtedly smaller than any lossless compression format, and the result of the well-known audio technology forum Hydrogen Audio test is based on the famous audio technology forum Hydrogen Audio. It is not the best sound quality, but it is the only format that can get better sound quality in various bit rates, and is also one of the fastest density compression formats with the fastest encoding speed.
So why do so many people think the sound quality of MP3 is relatively poor? In fact, in addition to people used to play MP3 software and equipment, there is a problem, more due to the quality of the sound source of MP3, and the processing of the sound source and the MP3 production method are incorrect. As long as you have a good source and master the correct production method, you can make high quality MP3 files.
The MP3 encoder converts the CD record, audio data on the DVD to the MP3 file, actually a process of re-encoding audio data with MP3 compression format. The quality and coding of MP3 encoding depends on the encoder. In other words, the MP3 encoder is determined whether we can make high quality MP3. There are currently many MP3 encoders available, but music enthusiasts with a certain understanding of MP3 compression technology will not hesitate to choose the Lame encoder. LAME encoding the original auditory psychological model combines VBR, ABR and other coding modes, allowing you to choose your own MP3 encoding effect and file size. It works with numerous audio processing software, allowing you to directly encode the songs on the CD record or other audio formats on the CD record on the common digital audio processing software.
Lame Developer (www.mp3dev.org) only provides the source code of the encoder, you need to run version, you can go to http://www.hot.e/smpman/mp3/ download. The encoder can run in the command line or for other audio processing software calls, and which encoding mode and bit rate to use are determined by the parameters. Since the Lame encoder has dozens of optional parameters, you will be quite complicated in accordance with these parameters. Therefore, this author is not prepared to introduce these coded parameters one by one, and only introduce a few sets of parameters for the encoder preset. Although you can detect the encoded parameters in some audio processing software, you will still need your own specified parameters in the command line state and most of the audio processing software, in order to get the best MP3 encoding effect, All MP3 methods in this article emphasize the use of the LAME encoder.
CBR preset parameters
The CBR (Constant Bit Rate) encoding mode uses constant bit rate, so-called constant bit rate, that is, the MP3 file using this encoding mode is fixed per second, and this coding mode has the advantage of being compressed, The disadvantage is that the compression efficiency is not high. The commonly used CBR preset parameters have the following: "- Alt-Preset Insane" and "--alt-preset CBR 320" parameters are the same, which makes the encoder use 320 kbps constant bit rate, due to 320kbps is lame. The highest bit rate encoded, so the MP3 file after the encoding is the highest, but the file volume will also be the largest; "- Alt-Preset CBR
The VBR (Variable Bit Rate) mode is dynamic bit rate, that is, this encoding mode is variable, encoded when encoded when the encoder is determined according to the audio data, and the audio data wave is complicated. The use of high bits is encoded, and the relatively low bit rate is used in a simple time. Its disadvantage is that the encoding is slower, the advantages are high compression efficiency, and the size of the file size is the current most popular MP3 encoding mode while ensuring quality. Common VBR preset parameters have the following four: "- Alt-Preset Extreme" is a VBR encoding scheme 220 to 270 kbps, and the sound quality is close to the highest quality 320Kbps CBR encoding file, but the file is 25%; "- Alt-Preset Standard "is a VBR coding scheme, which is about 180 to 220 kbps. It is equipped with sound quality and file size;" - Alt-Preset Fast Extreme is between the two programs, the sound quality is poor, the file Bighter than the second solution; parameters "- alt-preset fast standard" with it, compressing speeds than "-alt-preset standard" scenario, the file is also large.
ABR preset parameters
The APERAGE bit Rate mode uses average bit rate, which uses a paragraph of the low frequency and insensitive frequencies of the encoded content in a specified average bit rate. The relatively low bit rate, high frequency and high-speed dynamic performance paragraphs use a high bit rate. Most of the audio data is encoded using the specified bit rate during the encoding process, and the remaining portion is optimized by dynamic adjustment. At the same bit rate, the ABR encoded MP3 file is much different from the CBR encoded file size, but the sound quality increases a lot. Since most of the content uses the specified bit rate, the encoded speed is much faster than the VBR encoding mode, and can be used as a compromise option for VBR and CBR. "- Alt-Preset
Conversion audio file To convert other format audio files to MP3 files via the Lame encoder, you need an audio processing software that open this audio file and supports the LAME encoder, or first supports this audio file Convert it to WAV file format, then use the LAME encoder conversion directly. Such software can also find a plurality of plugins on audio players such as Winamp (www.winamp.com) and FOOBAR2000 (WWW. FooBar2000.org). If you want to know which audio processing software supports the LAME encoder, you can query on the Lame encoder developer's website (http://lame.sourceforge.net/links.html). Which is suitable for free LAME encoding software razorlame (http://www.dors.de/razorlame (http://www.dors.de/razorlame) and WinLame (WinLame.SourceForge.ne) in addition to setting up LAME encoding parameters in the graphical interface You can also open a variety of format audio files to convert it to an MP3 file, where WinLame can support AIFF, IFF, AU, WAV, OOG, MAT, MP2, and the like common audio file formats. Use WinLame
Download installation and run WinLame, click the Open button on the main interface of WinLame, select the audio file you want to convert, or drag the audio file on the main interface of WinLame, and then click "Next" to enter the next Select Input format . Note that you can drag multiple audio files to add them to WinLame, or you can select multiple audio files while selecting files when you click Open Buttons, or drag more and open files to add audio files that will be handled simultaneously. WinLame.
On the "Output Setting" page of the output format, the software uses the Lame Encler MP3 file output by default, you need to specify the folder path for the output conversion to save the MP3 file after the output conversion, or select "Use Input File's Folder AS The Output Location checkbox stores the converted MP3 file directly in the folder where the source file is located. If you need to select the "After Encoding, Do this" check box, then select all audio files on the drop-down menu, you need to turn off your computer or exit the software, or select the "Create Output Playlist" check box as All converted MP3 files creates a playlist.
After selecting the output format, click "Next" to enter the next "presets" page, WinLame will provide multiple preset parameters of the Lame encoder for you to choose, after selecting the encoding mode, you can go to the next "Encoding" page Click Start The button starts to switch. But if you are ready to convert a large number of audio files, and the computer has a relatively low configuration, it is recommended that you use the "Thread Prior" option before starting the conversion, drag the slider to the left to reduce the priority of the software processing thread, avoiding the process of conversion The computer cannot do other operations. The CD Record MP3 is to convert the music in the CD record into high-quality MP3 files. The key to success or failure is to extract the digital audio information on the CD record, consider us to use the Lame encoder, we should choose A software that can minimize data correctness and can directly call the LAME encoder. There are currently more software that can meet the above two conditions, but the most popular is undoubtedly Exact Audio Copy (www.exactaudiocopy.de), which is not only capable of optical drive detection capabilities and multiple reading data and ensures data correctness. There are still many other advantages, in addition to being able to call various external encoders such as lame, directly extract the music on the CD record and encode into popular audio formats such as MP3, the software also provides burn, you can use it directly Copy the CD record, or copy the CD audio file that copies to the hard disk into a CD record. Use Exact Audio Copy
You can download the latest version of EAC to Exact Audio Copy, the first runtime software will automatically activate the configuration wizard after installation, so that you choose to read the speed or higher music quality, choose The backward guide will require you to put an audio CD in the optical drive to detect the quality and characteristics of the optical drive. The detected content includes: whether the optical disk drive has the ability to cache audio data, whether it has an accuracy stream feature and whether C2-level error detection is supported. Disc drive If the accuracy flow characteristics can avoid the problem of accurate positioning of the optical drive cannot rely on the sector flag. The C2-level error detection is capable of detecting the correctness of C2 encoding check data on the CD while reading data, thereby automatically rereading when an error occurs, and these functions have a significant help for the correctness of the data. If the result of the detection shows that your optical drive is too bad, it is recommended that you replace a disc drive that is more suitable for MP3.
After the setting is completed, place the CD record into the optical drive, and the EAC will automatically read the CD record and display the track information contained in the record. If your record is a genuine, you can also select "Get CD Information" and "Remote" option from the Database (Database "menu. After selecting EAC will be able to automatically Query the information of CD records online, the query will display the names and album names of each song, when encoding the audio CD as the MP3 file, the EAC will use this information to automatically name and add song names for each MP3 file. And other information.
Next, you can select "Compressed Options" on the "EAC" menu on the EAC main interface, switch to the External Compression Program tab and select the "Use Export Compression" in the Compression Options dialog. , Select "Lame MP3 Encoder" on the "Parameter Delivery Scheme" drop-down menu, click the "Browse" button to find the installed Lame Encler when you download or install EAC, then follow your own needs drop-down menu Select the compression mode to use, or the encoding parameters of the LAME encoder within the "appended command line parameter" input box. After setting, click the Confirm to close the dialog to return to the EAC main interface, click the MP3 button on the EAC main interface and select the stored location to convert the CD record into MP3.
In addition, if the EAC successfully queries the CD on the Internet, you can also select the "Use ID3 Tag" check box in the External Compression Program tab on the "Compressed Options" tab, and then switch to " ID3 Label tab Definition How to add a label, let EAC automatically name and set the song name, album name, etc. when converting MP3 files, and sets ID3 TAG data such as the song name, album name.
Conversion VCD Audio If you want to make the audio portion in the VCD movie into the MP3 file unless you can't see a file in the computer, you can't see the VCD of a file, otherwise, do not simply use the player software to play in the player software. The VCD sound recording is converted. This method requires a VCD movie that needs to be changed. The sound quality will inevitably lose. The audio quality of the VCD is not very high. The effect of recording is poor. To ensure the quality of the converted MP3 file, you need to extract the audio of the VCD without affecting the sound quality, and then convert it through the LAME editor to MP3 file.
TMPGENC
We can decompose the DAT files in the VCD through the Victorial Editing Software TmpGenc (www.tmpgenc.net), store the audio information in which the audio information is stored as a separate audio file, and then convert it to the software described above. MP3 file. Download the installation and open TmpGenc, click the "File" menu to select the MPEG Tool, click the Decomposition button in the MPEG Tool dialog, click the "View" button next to the "Input" button to select the VCD CD The DAT file, the "MPEG Tool" dialog box will display the video and audio stream included in the file, double-click the audio stream of "Audio", the software will pop up a file path selection box allows you to choose the store. After selecting, click the confirmation button, the software will follow your choice to store the audio stream as a digital audio file in an MP2 format. The MP2 format is a commonly used multimedia file format, you can refer to the software described above to convert the audio file section, and processed according to your needs.
Enter the source of the sound source If you want to convert the sound source input through the sound card "line-in" input interface or "MIC" microphone interface to the MP3 file, first we need to use a software to record the sound source input, and then hand it over to the MP3 encoder. Conversion. Since the recording program cannot be guaranteed to start with the input audio, it is also necessary to make a simple editor after the recording, so we must ask the software that can provide audio file editing. There are many software capable of achieving these two functions, professional audio processing software Adobe Audition (www. Adobe.com) is a good choice, the predecessor of the software is a revitalized audio processing software product Cool Edit, except for recording And edit audio files, can also be used to convert various audio formats.
Use Adobe Audition
You can download Audition on Adobe's website (www. Adobe.com), first open the Adobe Audition software for the first time after installation, you will automatically transfer an audio processing example, do not let the green-green operation interface frightened, actually use methods Not complicated. First of all, you should click the "File" menu to create a new task. In the pop-up "New Waveform" dialog box, set "Sample Rate" to 44100 Hz, "Channels" is "Stereo", "resolution" is 16bit, then click the "OK" button to return Adobe Audition. Click the "Options" menu to select the "Windows Recording Mixer" command to open the System Volume Control dialog box, click the "Options" menu in the dialog box to select "Properties", in the "Volume Adjustment" column in the Properties dialog Select "Recording", select the input device for recording, such as "input line" or "microphone" in the "Show Line Volume Control" list, and then click the "OK" button to return to the volume control dialog box, adjust the input device The corresponding slider sets the volume size. After adjustment, close the dialog Returns Adobe Audition and click the "TRACK1" section of the window "TRACK1" section, click the "Record" button on the bottom toolbar to start recording. And open the input device to start entering audio information for recording. After completing the recording, click the "STOP" button under Adobe Audition to stop, then you can click the "Play" button in the toolbar to play back the sound record effect, then press the "F12" button on the keyboard to make the software in the interface On the right, the waveform display window is displayed. In the right waveform window of the operation interface, locate or drag the selected test playback effect, find the place where the audio information is started, and the mouse is dragged to select the blank section of the audio signal, click "Edit" menu Select "Delete Silence" to delete it, edit it, click "Edit" menu to select "Save As" and select "Save Type" for WAV, store recorded audio data as a WAV file, and then WAV file Encoding the software such as WinLame is MP3 file. Note that Adobe Audition also provides options that are stored as MP3 formats, but it is not a Lame encoder. There are many types of conversion sound sources of other sound sources, where we cannot introduce the MP3 method, but the method of actually conversion also has a certain rule. First, for various audio format conversion problems, there are many software supporting multiple audio formats and outputting MP3, and because it is possible to transfer in WAV format, there is almost no one of the audio formats that cannot be converted to MP3. Even if the software supports this format, such as the APE compression format, we can still use the Monkey's Audio (www.monkeysaudio.com) that created the audio format and the FOOBAR2000 player supported by playing APE, or install Monkey's Audio installation. The "APE.FLT" file under the "Tools" subdirectory in the directory is copied to the Adobe Audition installation directory, allowing Adobe Audition to support the APE format to open files and convert to common file formats such as WAV.
For audio in videos such as VCD, DVD, most of the software that can be edited for these video provides the function of separating audio data, using this feature we can store the audio data to an audio file. In addition, we can also extract audio information using professional audition, such as the professional audition, such as the DAT file or other avi video in the VCD, you can click "Audio from Video File ..." in Adobe Audition menu. , Then select the video file to extract audio information, you can extract the audio information in the video file, then store it as a common file format such as WAV, and then convert it to the MP3 file using the LAME encoder. Lossless compression and lossless compression lossless compression also referred to as redundancy compression, which uses data statistically redundant compression, which is exactly the same as the mathematics is a reversible operation, and the data before the compression encoding is identical. There is no data loss problem is the advantage of lossless compression, so it is widely used in text, program, fingerprint images, medical images, etc. need to complete the data of data. However, this compression method cannot obtain a relatively large compression ratio due to data statistics redundancy, and the general compression ratio is only 2: 1 to 5: 1.
The damaged compression method is also called the information quantity compression. This compression method utilizes human vision or human hearing to the image or sound of certain frequency components in the image or sound, from the original data, the human visual or human hearing is not Sensitive data removal to achieve the purpose of compression. It is not possible to completely restore the original data is the shortcomings with the maximum loss compression method, but the loss of the loss is smaller in understanding the original image or listening to the original sound, but there is a much larger compression ratio, therefore, there is a wide application of loss compression Compression of voice, image, and video data.
