✨ feat：添加预览视频指令，视频关键帧提取功能

- 此提交引入了一项新功能，允许使用FFmpeg从视频中提取关键帧。
- `extractKeyframes` 函数已被添加到 `ffmpeg-util.js` 以处理提取过程。
- `tools.js` 文件已更新以包含新功能，使用户能够预览视频的关键帧。
- `readCurrentDir` 函数已从 `file.js` 导入，以读取关键帧目录的内容。

apps/tools.js

@@ -83,7 +83,14 @@ import {
     truncateString,
     urlTransformShortLink
 } from "../utils/common.js";
-import { checkAndRemoveFile, deleteFolderRecursive, getMediaFilesAndOthers, mkdirIfNotExists } from "../utils/file.js";
+import { extractKeyframes } from "../utils/ffmpeg-util.js";
+import {
+    checkAndRemoveFile,
+    deleteFolderRecursive,
+    getMediaFilesAndOthers,
+    mkdirIfNotExists,
+    readCurrentDir
+} from "../utils/file.js";
 import GeneralLinkAdapter from "../utils/general-link-adapter.js";
 import { LagrangeAdapter } from "../utils/lagrange-adapter.js";
 import { contentEstimator } from "../utils/link-share-summary-util.js";
@@ -2459,6 +2466,21 @@ export class tools extends plugin {
                     await uploadTDL(path, this.isOverseasServer(), this.proxyAddr);
                     e.reply("✈️ 已发送一份到您的小飞机收藏夹了！");
                 })
+            } else if (e.msg.startsWith("预览视频")) {
+                // 预览视频逻辑
+                const keyframesPath = this.getCurDownloadPath(e) + "keyframes";
+                await mkdirIfNotExists(keyframesPath);
+                await extractKeyframes(path, keyframesPath);
+                const keyframes = await readCurrentDir(keyframesPath);
+                // logger.info(keyframes);
+                e.reply(Bot.makeForwardMsg(keyframes.map(keyframe => {
+                    return {
+                        message: segment.image(keyframesPath + "/" + keyframe),
+                        nickname: e.sender.card || e.user_id,
+                        user_id: e.user_id,
+                    };
+                })))
+                return;
             }
             // 正常发送视频
             if (videoSize > videoSizeLimit) {

utils/ffmpeg-util.js

@@ -0,0 +1,23 @@
+import path from 'path';
+import { exec } from 'child_process';
+
+// 写一个执行ffmpeg提取视频关键帧的函数，例如：ffmpeg -i input.mp4 -vf "select=eq(pict_type\,I)" -vsync drop -vframes 5 -qscale:v 2 keyframes\keyframe_%03d.jpg
+export async function extractKeyframes(inputFilePath, outputFolderPath, frameCount = 20) {
+    return new Promise((resolve, reject) => {
+        // 创建输出文件夹路径
+        const outputFilePattern = path.join(outputFolderPath, 'keyframe_%03d.jpg');
+
+        // 构建FFmpeg命令
+        const ffmpegCommand = `ffmpeg -i "${inputFilePath}" -vf "select=eq(pict_type\\,I)" -vsync drop -vframes ${frameCount} -qscale:v 2 "${outputFilePattern}"`;
+
+        // 执行FFmpeg命令
+        exec(ffmpegCommand, (error, stdout, stderr) => {
+            if (error) {
+                reject(`[R插件][ffmpeg工具]执行FFmpeg命令时出错: ${ stderr }`);
+            } else {
+                logger.info(`[R插件][ffmpeg工具]关键帧成功提取到 ${ outputFolderPath }`);
+                resolve(outputFolderPath);
+            }
+        });
+    });
+}