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      <base href="https://bugs.webkit.org/">
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    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - MP3 decoder ignoring XIPH header related to encoder delay and padding information"
   href="https://bugs.webkit.org/show_bug.cgi?id=228215">228215</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>MP3 decoder ignoring XIPH header related to encoder delay and padding information
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>WebKit
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>WebKit Nightly Build
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>Unspecified
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Unspecified
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>Normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P2
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>Web Audio
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>webkit-unassigned@lists.webkit.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>jean-yves.avenard@apple.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>cdumez@apple.com
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Consider the following case:

STR:

1- Open <a href="https://jyavenard.github.io/htmltests/tests/webaudio/decodeAudioData.html">https://jyavenard.github.io/htmltests/tests/webaudio/decodeAudioData.html</a>
2- Select half-a-second-48000.mp3 at the bottom of the list
3- Click on play

Safari will show 26496 frames 0.552s.

This file is exactly .5s long and made of 24000 frames.

It contains a XIPH header that provides the encoder delay and padding information.

Chrome and Firefox properly parse those MP3 which results in a continuous audio stream when looping. On Safari you can here the incorrectly generated blank frames.

The ability the produce frame-exact content is important for web audio applications. 

WebKit uses ExtAudioFileRead to demux and decode this file and it returns too many frames.</pre>
        </div>
      </p>


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