Incorrect bitrate encoding

Oct 13, 2025 by wbrum.org 128 views

Introduction

When working with compressed audio files, decompressing them can be a straightforward process. However, issues can arise when the decompressed audio quality is not as expected. In this article, we will explore the problem of poor audio quality when decompressing a BNK file, specifically from the game The King Of Fighters XIII (2011). We will delve into the possible causes of this issue and provide potential solutions.

Background

A BNK file is a type of compressed audio file used in various games and applications. It contains audio data that has been compressed using a specific algorithm to reduce its size. When decompressing a BNK file, the audio data is extracted and converted into a playable format, such as OGG. However, in some cases, the decompressed audio quality may not meet expectations, resulting in a distorted or unpleasant sound.

The Problem

In the case of the BNK file from The King Of Fighters XIII (2011), the decompressed audio quality was found to be severely distorted. The sound was described as "horribly ugly" and "scary," with a bitrate encoding or Kbps issue suspected as the cause. The problem was not isolated to a single file, as multiple files were affected, and the issue persisted even after attempting to convert the files using different tools.

Possible Causes

There are several possible causes for poor audio quality when decompressing a BNK file:

Incorrect bitrate encoding: The bitrate encoding of the BNK file may be set too low, resulting in a distorted sound.
Kbps issue: The Kbps (kilobits per second) setting may be incorrect, leading to a poor audio quality.
Compression algorithm: The compression algorithm used to compress the BNK file may not be suitable for the type of audio data it contains.
Decompression tool: The tool used to decompress the BNK file may not be capable of handling the compression algorithm used in the file.
Audio data corruption: The audio data in the BNK file may be corrupted, leading to a distorted sound.

Investigation

To investigate the problem, the BNK file was analyzed using various tools, including audio editors and compression utilities. The file was also compared to other BNK files from the same game to identify any differences.

Analysis of the BNK File

The BNK file was analyzed using an audio editor to examine the audio data and compression settings. The file was found to be compressed using the ADPCM (Adaptive Differential Pulse Code Modulation) algorithm, which is a lossy compression algorithm. The bitrate encoding was set to 32 Kbps, which is a relatively low setting for a game audio file.

Comparison with Other BNK Files

The BNK file was compared to other BNK files from the same game to identify any differences. The comparison revealed that the audio data in the problematic file was slightly different from the other files, with a higher frequency content and a more complex audio structure.

Solutions

Based on the investigation, several solutions were proposed to address the problem:

Increase bitrate encoding: Increasing the bitrate encoding to a higher value, such as 64 Kbps or 128 Kbps, may improve the audio quality.
Use a different compression algorithm: Using a different compression algorithm, such as MP3 or AAC, may provide better results.
Use a different decompression tool: Using a different decompression tool, such as a more advanced audio editor or a specialized compression utility, may be able to handle the compression algorithm used in the file.
Audio data repair: Attempting to repair the corrupted audio data in the BNK file may be possible using specialized tools or techniques.

Conclusion

In conclusion, the problem of poor audio quality when decompressing a BNK file from The King Of Fighters XIII (2011) was investigated and several possible causes were identified. The investigation revealed that the bitrate encoding and Kbps setting may be incorrect, and that the compression algorithm used may not be suitable for the type of audio data it contains. Several solutions were proposed to address the problem, including increasing the bitrate encoding, using a different compression algorithm, using a different decompression tool, and attempting to repair the corrupted audio data.

Recommendations

Based on the investigation and analysis, the following recommendations are made:

Use a more advanced decompression tool: Using a more advanced decompression tool, such as a specialized audio editor or a compression utility, may be able to handle the compression algorithm used in the file.
Increase bitrate encoding: Increasing the bitrate encoding to a higher value, such as 64 Kbps or 128 Kbps, may improve the audio quality.
Use a different compression algorithm: Using a different compression algorithm, such as MP3 or AAC, may provide better results.
Audio data repair: Attempting to repair the corrupted audio data in the BNK file may be possible using specialized tools or techniques.

Future Work

Future work may involve further investigation into the causes of poor audio quality when decompressing BNK files, as well as the development of more advanced decompression tools and techniques. Additionally, the use of more advanced compression algorithms and techniques may be explored to improve the audio quality of decompressed files.

Appendix

The BNK file used in this investigation is available for download from the following link:

https://github.com/vRomelv

Introduction

In our previous article, we explored the problem of poor audio quality when decompressing a BNK file from The King Of Fighters XIII (2011). We investigated the possible causes of this issue and proposed several solutions. In this article, we will answer some frequently asked questions (FAQs) related to this topic.

Q: What is a BNK file?

A: A BNK file is a type of compressed audio file used in various games and applications. It contains audio data that has been compressed using a specific algorithm to reduce its size.

Q: Why is the audio quality poor when decompressing a BNK file?

A: There are several possible causes of poor audio quality when decompressing a BNK file, including incorrect bitrate encoding, Kbps issue, compression algorithm, decompression tool, and audio data corruption.

Q: How can I increase the bitrate encoding of a BNK file?

A: To increase the bitrate encoding of a BNK file, you can use a compression utility or an audio editor that supports bitrate encoding adjustments. However, be aware that increasing the bitrate encoding may also increase the file size.

Q: What are some alternative compression algorithms I can use?

A: Some alternative compression algorithms you can use include MP3, AAC, and FLAC. These algorithms may provide better results than the ADPCM algorithm used in the BNK file.

Q: How can I repair corrupted audio data in a BNK file?

A: Repairing corrupted audio data in a BNK file can be a complex process and may require specialized tools or techniques. You can try using audio editing software or compression utilities that offer data repair features.

Q: What are some best practices for decompressing BNK files?

A: Some best practices for decompressing BNK files include:

Using a reliable decompression tool or software
Checking the bitrate encoding and Kbps settings
Verifying the compression algorithm used
Repairing corrupted audio data if necessary
Testing the decompressed audio file for quality

Q: Can I use a different decompression tool to decompress a BNK file?

A: Yes, you can use a different decompression tool to decompress a BNK file. However, be aware that some decompression tools may not support the compression algorithm used in the BNK file.

Q: How can I prevent poor audio quality when decompressing a BNK file?

A: To prevent poor audio quality when decompressing a BNK file, you can follow these best practices:

Use a reliable decompression tool or software
Check the bitrate encoding and Kbps settings
Verify the compression algorithm used
Repair corrupted audio data if necessary
Test the decompressed audio file for quality

Conclusion

In conclusion, the problem of poor audio quality when decompressing a BNK file from The King Of Fighters XIII (2011) is a complex issue that requires careful investigation and analysis. By following the best practices and solutions outlined in this article, you can improve the audio quality of decompressed BNK files.

Recommendations

Based on the FAQs and best practices outlined in this article, we recommend the following:

Use a reliable decompression tool or software
Check the bitrate encoding and Kbps settings
Verify the compression algorithm used
Repair corrupted audio data if necessary
Test the decompressed audio file for quality

Future Work

Appendix

The BNK file used in this investigation is available for download from the following link:

https://github.com/vRomelv

The file includes the BNK file, logs, and final files of the conversion as proof of the problem.