Optimizing Audio
assignment 1
Diamonds on the Soles of Her Shoes
For this assignment, I chose a 17-second clip of Paul Simon's song Diamonds on the Soles of her Shoes. To begin with, I converted it to mono, normalized it and faded it in and out. Here is the clip:
Optimizing the Clip
After that, I tried a number of different file formats and settings in an attempt to find what works best for a web page. Here are the results:
Wav Files
| File Name | File Format & Codec | Sample Rate | Bit Depth | Bitrate | File Size | Usability |
|---|---|---|---|---|---|---|
| diamondsClip.wav | wav PCM |
44100 Hz | 32-bit | 1411 kbps | 2.99 MB | good sound quality; too large for the web |
| diamondsClip_01.wav | wav PCM |
22050 Hz | 16-bit | 352 kbps | 774 KB | No noticeable change in quality, but smaller file size |
| diamondsClip_02.wav | wav PCM |
11025 HZ | 8-bit | 88 kbps | 199 KB | noticeable static; not good quality |
| diamondsClip-03.wav | wav PCM |
11025 Hz | 16-bit | 176 kbps | 391 KB | slightly muffled, but probably good enough sound; still a large file size |
| diamondsClip-04.wav | wav PCM |
22050 HZ | 8-bit | 176 kbps | 391 KB | noticeable static; not good quality |
Summary:
For wav files, the audio quality changes considerably depending on the settings. All of the wav files with good enough sound quality are probably too large to be used on a web page.
MP3 Files
| File Name | File Format & Codec | Sample Rate | Bit Depth | Bitrate | File Size | Usability |
|---|---|---|---|---|---|---|
| diamondsClip_06.mp3 | MP3 MP3 |
44100 Hz | 32-bit | 192 kbps | 426 KB | sound great; still quite large |
| diamondsClip_07.mp3 | MP3 MP3 |
22050 Hz | 16-bit | 48 kbps | 112 KB | sounds great; much smaller Is it small enough? |
| diamondsClip_08.wav | MP3 MP3 |
22050 HZ | 16-bit | 32 kbps | 78 KB | sounds a bit muffled |
| diamondsClip-09.wav | MP3 MP3 |
11025 Hz | 16-bit | 20 kbps | 52.2 KB | very muffled |
Summary:
It's easier to get smaller MP3 files without losing too much quality. For me, diamondsClip_07.mp3 was the best of this format. The bitrate of 48 kbps seemed to be the lowest without losing too much sound quality.
OGG Files
| File Name | File Format & Codec | Sample Rate | Bit Depth | Bitrate | File Size | Usability |
|---|---|---|---|---|---|---|
| diamondsClip_10.wav | ogg Vorbis |
44100 Hz | 16-bit | 100% 705 kbps |
476 KB | good sound quality; large file size |
| diamondsClip_12.wav | ogg Vorbis |
22050 Hz | 16-bit | 60% 352 kbps |
142 KB | sounds good; smaller file size |
| diamondsClip_13.wav | ogg Vorbis |
22050 HZ | 16-bit | 40% 352 kbps |
115 KB | smaller size; still sounds good |
| diamondsClip-14.wav | ogg Vorbis |
22050 Hz | 16-bit | 20% 352 kbps |
97 KB | still sounds fine to me |
| diamondsClip-16.wav | ogg Vorbis |
22050 HZ | 8-bit | 20% 252 kbps |
92 KB | not much smaller; noticeable static |
Summary:
Even at a low quality of 20%, the ogg files still sounded fine to me, and the file size was even smaller than the most usable mp3.
This is probably the most usable clip of the bunch with good sound quality and only a 97 KB file size - diamondsClip_14.ogg
And this is one of the least usable ones with 8-bit bit depth and a quality of 20% - diamondsClip_16.ogg