phantomjs屏幕截图和ffmpeg帧丢失

我在从phantomjs网站截图制作视频时遇到问题

phantomjs并没有在同一秒内对所有帧进行截图，甚至不是所有的秒，都有大量的丢失帧

结果是高速视频播放，视频效果有很多跳跃

test.js:

var page = require('webpage').create(),
    address = 'http://raphaeljs.com/polar-clock.html',
    duration = 5, // duration of the video, in seconds
    framerate = 24, // number of frames per second. 24 is a good value.
    counter = 0,
    width = 1024,
    height = 786;
        frame = 10001;

page.viewportSize = { width: width, height: height };

page.open(address, function(status) {
    if (status !== 'success') {
        console.log('Unable to load the address!');
        phantom.exit(1);
    } else {
        window.setTimeout(function () {
            page.clipRect = { top: 0, left: 0, width: width, height: height };

            window.setInterval(function () {
                counter++;
                page.render('newtest/image'+(frame++)+'.png', { format: 'png' });
                if (counter > duration * framerate) {
                    phantom.exit();
                }
            }, 1/framerate);
        }, 200);
    }
});

fmpeg -start_number 10001 -i newtest/image%05d.png -c:v libx264 -r 24 -pix_fmt yuv420p out.mp4

这将创建120个图像，这是正确的计数，但当您逐个查看图像时，您将看到许多重复的相同内容和许多缺少的帧

ffmpeg:

var page = require('webpage').create(),
    address = 'http://raphaeljs.com/polar-clock.html',
    duration = 5, // duration of the video, in seconds
    framerate = 24, // number of frames per second. 24 is a good value.
    counter = 0,
    width = 1024,
    height = 786;
        frame = 10001;

page.viewportSize = { width: width, height: height };

page.open(address, function(status) {
    if (status !== 'success') {
        console.log('Unable to load the address!');
        phantom.exit(1);
    } else {
        window.setTimeout(function () {
            page.clipRect = { top: 0, left: 0, width: width, height: height };

            window.setInterval(function () {
                counter++;
                page.render('newtest/image'+(frame++)+'.png', { format: 'png' });
                if (counter > duration * framerate) {
                    phantom.exit();
                }
            }, 1/framerate);
        }, 200);
    }
});

fmpeg -start_number 10001 -i newtest/image%05d.png -c:v libx264 -r 24 -pix_fmt yuv420p out.mp4

我知道这个脚本和ffmpeg命令并不完美，因为我在没有lucky的情况下做了数百次更改，并且我失去了对正确设置的理解

有人指导我修这个吗

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谢谢大家

有人知道吗？你找到解决办法了吗？这是我找到的最接近答案的东西