var slider = $("#gallery").bxSlider({
adaptiveHeight:true,
auto:true,
autoStart:true,
autoControls:true,
video:true,
onSlideAfter: function(slide){
if (slide.find("iframe:first").length) {
slider.stopAuto();
}
}
});
You might also be able to use something like slide.find("div.fluid-width-video-wrapper:first") if you use iframes for other things in the in the slider.
Source
----Update----
var slider = $('.bxslider').bxSlider({
onSlideAfter: function(slide, oldindex, currentSlide){
oldSlide = $( '.bxslider > li:nth-child(' + (oldindex+1) + ')');
youtubeVideo = oldSlide.find('iframe[src*=youtube]');
if ( youtubeVideo.length ) {
youtubeVideo.get(0).contentWindow.postMessage('{"event":"command","func":"pauseVideo","args":""}','*');
}
}
});
Source
----Edit----
Also make sure to add ?enablejsapi=true
to the the iframe src, otherwise the above JavaScript will not work (source).