The article explores YouTube's audio quality by providing several blind listening tests comparing different formats, including Opus 128 kbps (YouTube Music), AAC 128 kbps (regular YouTube), and original, lossless WAV files. The author concludes that while discerning the difference between lossy and lossless audio on YouTube can be challenging, it is possible, especially with higher-quality headphones and focused listening. Opus generally performs better than AAC, exhibiting fewer compression artifacts. Ultimately, while YouTube's audio quality isn't perfect for audiophiles, it's generally good enough for casual listening, and the average listener likely won't notice significant differences.
This post provides a high-level overview of compression algorithms, categorizing them into lossless and lossy methods. Lossless compression, suitable for text and code, reconstructs the original data perfectly using techniques like Huffman coding and LZ77. Lossy compression, often used for multimedia like images and audio, achieves higher compression ratios by discarding less perceptible data, employing methods such as discrete cosine transform (DCT) and quantization. The post briefly explains the core concepts behind these techniques and illustrates how they reduce data size by exploiting redundancy and irrelevancy. It emphasizes the trade-off between compression ratio and data fidelity, with lossy compression prioritizing smaller file sizes at the expense of some information loss.
Hacker News users discussed various aspects of compression, prompted by a blog post overviewing different algorithms. Several commenters highlighted the importance of understanding data characteristics when choosing a compression method, emphasizing that no single algorithm is universally superior. Some pointed out the trade-offs between compression ratio, speed, and memory usage, with specific examples like LZ77 being fast for decompression but slower for compression. Others discussed more niche compression techniques like ANS and its use in modern codecs, as well as the role of entropy coding. A few users mentioned practical applications and tools, like using zstd for backups and mentioning the utility of brotli. The complexities of lossy compression, particularly for images, were also touched upon.
Summary of Comments ( 2 )
https://news.ycombinator.com/item?id=42901182
HN users largely discuss their own experiences with YouTube's audio quality, generally agreeing it's noticeably compressed but acceptable for casual listening. Some point out the loudness war is a major factor, with dynamic range compression being a bigger culprit than the codec itself. A few users mention preferring specific codecs like Opus, and some suggest using third-party tools to download higher-quality audio. Several commenters highlight the variability of audio quality depending on the uploader, noting that some creators prioritize audio and others don't. Finally, the limitations of perceptual codecs and the tradeoff between quality and bandwidth are discussed.
The Hacker News post titled "YouTube Audio Quality – How Good Does It Get?" with the link https://news.ycombinator.com/item?id=42901182 has several comments discussing various aspects of YouTube's audio quality.
Many commenters agree that YouTube's audio quality is generally considered "good enough" for the average listener, especially for casual music listening and spoken word content. However, for audiophiles and those with higher-end audio equipment, the limitations become apparent. Opus 128kbps, the common codec used by YouTube, is highlighted as a significant compromise. While efficient and adequate for most, it introduces perceptible compression artifacts that diminish the listening experience compared to lossless or higher bitrate formats.
Several comments focus on the specific example in the linked article, highlighting that differentiating between the original and the YouTube version isn't always easy, further reinforcing the idea that YouTube's quality is sufficient for many. However, other commenters argue that the difficulty of the test doesn't negate the underlying quality difference and that subtle compression artifacts still exist, impacting the overall experience.
The discussion also branches into related topics, such as:
A particularly compelling thread emerges from discussions about "transparent" compression, with users debating whether the compression artifacts introduced by Opus are truly imperceptible. This leads to a deeper conversation about the subjectivity of audio quality and the role of individual perception and equipment in evaluating these differences.
Overall, the comments paint a picture of YouTube's audio quality as a pragmatic compromise between bandwidth efficiency and acceptable listening experience for the vast majority of users, while acknowledging the limitations for critical listeners and audiophiles. The comments don't definitively conclude whether the quality is "good" or "bad," but rather offer diverse perspectives reflecting the varying needs and priorities of listeners.