webpmux对webp动图进行解序列帧，再将序列帧合并成webp动图

package com.immomo.kaka.vesta.service;

import java.io.IOException;
import java.io.InputStream;
import java.util.Objects;

/**
 * @author wangduanqing
 * @date 2021/05/13
 */
public class WebpMux {

    private final static String dir = "/Users/wangduanqing/Desktop/test/";

    public static void main(String[] args) throws IOException {
        String filePath = dir + "koubi.webp";
        InputStream is = Runtime.getRuntime().exec("webpmux -info " + filePath).getInputStream();
        String[] rows = new String(is.readAllBytes()).split("\n");
        int total = Integer.parseInt(rows[3].replace("Number of frames: ", ""));
        System.out.println("total frames: " + total);
        WebpMuxConfig[] webpMuxConfigs = new WebpMuxConfig[total];
        for (int i = 5; i < total + 5; i++) {
            webpMuxConfigs[i - 5] = splitRow(rows[i]);
        }
        for (int i = 0; i < total; i++) {
            Runtime.getRuntime().exec("webpmux -get frame " + (i + 1) + " " + filePath + " -o " + dir + (i + 1) + ".webp");
        }
        InputStream xx = Runtime.getRuntime().exec(buildCommand(webpMuxConfigs)).getInputStream();
        System.out.println(new String(xx.readAllBytes()));
    }

    private static String buildCommand(WebpMuxConfig[] webpMuxConfigs) {
        StringBuilder builder = new StringBuilder("webpmux ");
        for (int i = 0; i < webpMuxConfigs.length; i += 2) {
            builder.append("-frame ").append(dir).append(i + 1).append(".webp ");
            if (i == 0) {
                builder.append("+").append(webpMuxConfigs[i].duration);
            } else {
                builder.append("+").append(webpMuxConfigs[i].duration * 2);
            }
            builder
                .append("+").append(webpMuxConfigs[i].offsetX)
                .append("+").append(webpMuxConfigs[i].offsetY)
                .append("+").append(webpMuxConfigs[i].dispose)
                .append(webpMuxConfigs[i].blend).append(" ");
        }
        builder.append("-loop 0 ");
        builder.append("-o ").append(dir).append("koubi_2.webp");

        System.out.println(builder.toString());
        return builder.toString();
    }


    private static WebpMuxConfig splitRow(String row) {
        char[] chars = row.toCharArray();
        String[] items = new String[11];
        StringBuilder builder = new StringBuilder();
        int index = 0;
        for (char c : chars) {
            if (c != ' ') {
                builder.append(c);
            } else {
                if (builder.length() != 0) {
                    items[index++] = builder.toString();
                }
                builder.setLength(0);
            }
        }
        if (builder.length() != 0) {
            items[index] = builder.toString();
        }
        String dispose = Objects.equals("background", items[7]) ? "1" : "0";
        String blend = Objects.equals("no", items[8]) ? "-b" : "+b";
        return new WebpMuxConfig(items[4], items[5], Integer.parseInt(items[6]), dispose, blend);
    }

    /**
     * No.: width height alpha x_offset y_offset duration   dispose blend image_size  compression 1:   388   397   yes       64       64       42 background    no       6976 lossy
     */
    private static class WebpMuxConfig {

        private String offsetX;
        private String offsetY;
        private int duration;
        private String dispose;
        private String blend;

        public WebpMuxConfig(String offsetX, String offsetY, int duration, String dispose, String blend) {
            this.offsetX = offsetX;
            this.offsetY = offsetY;
            this.duration = duration;
            this.dispose = dispose;
            this.blend = blend;
        }
    }
}

命令参考：https://developers.google.com/speed/webp/docs/webpmux