synchronizing video and image playback

Hello, I would like to know how do I go about synchronizing the playback of a video and image slideshow?
I am using one XML file as below:

<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<images>
<items>
<channel1>
<video desc="Prisoner of Azkaban" flv="flv/azkaban.flv" item="2"/>
</channel1>

<channel2>
<images>images/ch2/ss310.jpg</images>
<images>images/ch2/ss001.jpg</images>
<images>images/ch2/ss002.jpg</images>

</channel2>
<channel3>
<images>images/ch3/ss308.jpg</images>
<images>images/ch3/ss007.jpg</images>
<images>images/ch3/ss008.jpg</images>
</channel3>
<channel4>
<messages>Item 1 message 1</messages>
<messages>Item 1 message 2</messages>
<messages>Item 1 message 3</messages>
</channel4>

</items>

<items>

<channel1>
<video desc="X Men 3" flv="flv/xmen3.flv" item="0"/>
</channel1>

<channel2>
<images>images/ch2/ss305.jpg</images>
<images>images/ch2/ss003.jpg</images>
<images>images/ch2/ss004.jpg</images>

</channel2>
<channel3>
<images>images/ch3/ss309.jpg</images>
<images>images/ch3/ss009.jpg</images>
<images>images/ch3/ss010.jpg</images>
</channel3>
<channel4>
<messages>Network Casting Test</messages>
</channel4>

</items>

<items>

<channel1>
<video desc="Fantastic Four" flv="flv/fantastic4.flv" item="1">
</channel1>
<channel2>
<images>images/ch2/ss306.jpg</images>
<images>images/ch2/ss005.jpg</images>
<images>images/ch2/ss006.jpg</images>
</channel2>
<channel3>
<images>images/ch3/ss307.jpg</images>
<images>images/ch3/ss011.jpg</images>
<images>images/ch3/ss012.jpg</images>
</channel3>
<channel4>
<messages>Hello, testing testing</messages>
</channel4>

</items>




</images>

What I would like to do is to have the play the items as a set. meaning when Channel 1's video is playing Channel 2-4 will be playing as well, they will be looping through from the first image/message to the last and then back to the first and keep looping till the video has finished playing. When the video has finished playing it will move to the next set of items and play through them as Items 1 did, and keep going through all the Items as a set till it reaches the end of the list where it will loop back to the beginning again, continuing it's cycle.

would appreciate any help,

Thank you in advance