ffmpeg.ts•16.6 kB
import ffmpeg from 'fluent-ffmpeg';
import { path as ffmpegPath } from '@ffmpeg-installer/ffmpeg';
import { promises as fs, statSync } from 'fs';
import path from 'path';
import { VideoInfo, ConversionOptions, ConversionProgress, QualityPreset } from '../types/index.js';
/**
* FFmpeg服务类 - 封装视频处理功能
*/
export class FFmpegService {
private static instance: FFmpegService;
private activeConversions = new Map<string, ConversionProgress>();
private constructor() {
// 设置ffmpeg可执行文件的路径，确保使用项目内的版本
ffmpeg.setFfmpegPath(ffmpegPath);
}
public static getInstance(): FFmpegService {
if (!FFmpegService.instance) {
FFmpegService.instance = new FFmpegService();
}
return FFmpegService.instance;
}
/**
* 获取视频文件信息
*/
async getVideoInfo(filePath: string): Promise<VideoInfo> {
return new Promise((resolve, reject) => {
ffmpeg.ffprobe(filePath, (err, metadata) => {
if (err) {
reject(new Error(`获取视频信息失败: ${err.message}`));
return;
}
try {
const stats = statSync(filePath);
const videoStream = metadata.streams.find(s => s.codec_type === 'video');
const audioStream = metadata.streams.find(s => s.codec_type === 'audio');
// 修复时长获取逻辑，特别是对WMV等格式
let duration = metadata.format.duration || 0;
// 如果format中没有时长信息，尝试从视频流中获取
if (!duration || duration === 0) {
if (videoStream && videoStream.duration) {
duration = parseFloat(videoStream.duration);
} else if (audioStream && audioStream.duration) {
duration = parseFloat(audioStream.duration);
}
}
// 如果还是没有时长，尝试通过帧数和帧率计算
if (!duration || duration === 0) {
if (videoStream && videoStream.nb_frames && videoStream.r_frame_rate) {
const frameCount = parseInt(videoStream.nb_frames);
const frameRate = this.parseFrameRate(videoStream.r_frame_rate);
if (frameCount > 0 && frameRate > 0) {
duration = frameCount / frameRate;
}
}
}
const videoInfo: VideoInfo = {
filePath,
format: metadata.format.format_name || '未知',
size: stats.size,
duration: duration,
};
if (videoStream) {
videoInfo.video = {
codec: videoStream.codec_name || '未知',
width: videoStream.width || 0,
height: videoStream.height || 0,
frameRate: this.parseFrameRate(videoStream.r_frame_rate),
bitrate: videoStream.bit_rate ? parseInt(videoStream.bit_rate) : null,
};
}
if (audioStream) {
videoInfo.audio = {
codec: audioStream.codec_name || '未知',
sampleRate: audioStream.sample_rate || 0,
channels: audioStream.channels || 0,
bitrate: audioStream.bit_rate ? parseInt(audioStream.bit_rate) : null,
};
}
resolve(videoInfo);
} catch (parseError) {
reject(new Error(`解析视频信息失败: ${parseError}`));
}
});
});
}
/**
* 转换视频格式
*/
async convertVideo(
inputPath: string,
outputPath: string,
options: ConversionOptions,
onProgress?: (progress: ConversionProgress) => void
): Promise<string> {
const taskId = this.generateTaskId();
// 检查输入文件是否存在
try {
await fs.access(inputPath);
} catch {
throw new Error(`输入文件不存在: ${inputPath}`);
}
// 确保输出目录存在
const outputDir = path.dirname(outputPath);
await fs.mkdir(outputDir, { recursive: true });
// 检查输出文件是否已存在
if (!options.overwrite) {
try {
await fs.access(outputPath);
throw new Error(`输出文件已存在: ${outputPath}`);
} catch (err: any) {
if (err.code !== 'ENOENT') {
throw err;
}
}
}
return new Promise((resolve, reject) => {
const progress: ConversionProgress = {
taskId,
inputPath,
outputPath,
progress: 0,
status: 'pending',
startTime: new Date(),
};
this.activeConversions.set(taskId, progress);
let command = ffmpeg(inputPath);
// 应用转换选项
command = this.applyConversionOptions(command, options);
command
.output(outputPath)
.on('start', (commandLine) => {
console.log('开始转换:', commandLine);
progress.status = 'processing';
onProgress?.(progress);
})
.on('progress', (progressInfo) => {
progress.progress = Math.round(progressInfo.percent || 0);
onProgress?.(progress);
})
.on('end', async () => {
try {
// 验证输出文件是否完整
await this.validateOutputFile(outputPath);
progress.status = 'completed';
progress.progress = 100;
progress.endTime = new Date();
this.activeConversions.delete(taskId);
onProgress?.(progress);
resolve(outputPath);
} catch (validationError: any) {
progress.status = 'failed';
progress.error = `输出文件验证失败: ${validationError.message}`;
progress.endTime = new Date();
this.activeConversions.delete(taskId);
onProgress?.(progress);
reject(new Error(`转换完成但文件验证失败: ${validationError.message}`));
}
})
.on('error', (err) => {
progress.status = 'failed';
progress.error = err.message;
progress.endTime = new Date();
this.activeConversions.delete(taskId);
onProgress?.(progress);
// 提供更详细的错误信息
let errorMessage = `视频转换失败: ${err.message}`;
// 针对常见错误提供解决建议
if (err.message.includes('moov atom not found')) {
errorMessage += '\n建议: 输入文件可能损坏或格式不完整，请检查源文件';
} else if (err.message.includes('Invalid data found')) {
errorMessage += '\n建议: 输入文件格式可能不受支持或文件已损坏';
} else if (err.message.includes('No such file or directory')) {
errorMessage += '\n建议: 请检查输入文件路径是否正确';
} else if (err.message.includes('Permission denied')) {
errorMessage += '\n建议: 请检查文件权限或确保输出目录可写';
} else if (err.message.includes('codec not found')) {
errorMessage += '\n建议: 缺少必要的编解码器，请检查FFmpeg安装';
}
reject(new Error(errorMessage));
})
.run();
});
}
/**
* 批量转换视频
*/
async batchConvert(
inputFiles: string[],
outputDir: string,
options: ConversionOptions,
onProgress?: (taskId: string, progress: ConversionProgress) => void
): Promise<string[]> {
const results: string[] = [];
for (const inputFile of inputFiles) {
const fileName = path.parse(inputFile).name;
const outputPath = path.join(outputDir, `${fileName}.${options.outputFormat}`);
try {
const result = await this.convertVideo(
inputFile,
outputPath,
options,
(progress) => onProgress?.(progress.taskId, progress)
);
results.push(result);
} catch (error) {
console.error(`转换文件失败 ${inputFile}:`, error);
throw error;
}
}
return results;
}
/**
* 获取转换进度
*/
getConversionProgress(taskId: string): ConversionProgress | undefined {
return this.activeConversions.get(taskId);
}
/**
* 应用转换选项到FFmpeg命令
*/
private applyConversionOptions(command: ffmpeg.FfmpegCommand, options: ConversionOptions): ffmpeg.FfmpegCommand {
// 根据输出格式设置合适的编解码器和参数
command = this.setCodecsForFormat(command, options.outputFormat);
// 应用质量预设
if (options.quality) {
command = this.applyQualityPreset(command, options.quality);
}
// 设置分辨率
if (options.resolution) {
command = command.size(`${options.resolution.width}x${options.resolution.height}`);
}
// 设置视频码率（仅在没有使用CRF时）
if (options.videoBitrate && !this.usesCRF(options.outputFormat)) {
command = command.videoBitrate(options.videoBitrate);
}
// 设置音频码率
if (options.audioBitrate) {
command = command.audioBitrate(options.audioBitrate);
}
// 设置帧率
if (options.frameRate) {
command = command.fps(options.frameRate);
}
// 确保完整复制所有流，避免时长截断
command = command.addOption('-avoid_negative_ts', 'make_zero');
command = command.addOption('-fflags', '+genpts');
// 添加更多稳定性选项
command = command.addOption('-max_muxing_queue_size', '1024');
return command;
}
/**
* 为不同格式设置合适的编解码器
*/
private setCodecsForFormat(command: ffmpeg.FfmpegCommand, format: string): ffmpeg.FfmpegCommand {
switch (format.toLowerCase()) {
case 'mp4':
command = command.videoCodec('libx264').audioCodec('aac');
command = command.addOption('-preset', 'medium');
command = command.addOption('-crf', '23'); // 高质量设置
// 修复MP4容器问题的关键参数
command = command.addOption('-movflags', '+faststart+frag_keyframe+empty_moov');
command = command.addOption('-f', 'mp4'); // 强制指定容器格式
// 确保兼容性
command = command.addOption('-pix_fmt', 'yuv420p');
command = command.addOption('-profile:v', 'high');
command = command.addOption('-level', '4.0');
break;
case 'avi':
command = command.videoCodec('libx264').audioCodec('aac');
command = command.addOption('-preset', 'medium');
command = command.addOption('-crf', '23');
command = command.addOption('-f', 'avi');
break;
case 'mov':
command = command.videoCodec('libx264').audioCodec('aac');
command = command.addOption('-preset', 'medium');
command = command.addOption('-crf', '23');
command = command.addOption('-movflags', '+faststart'); // 优化MOV播放
command = command.addOption('-f', 'mov');
break;
case 'webm':
command = command.videoCodec('libvpx-vp9').audioCodec('libopus');
command = command.addOption('-crf', '30');
command = command.addOption('-b:v', '0'); // 使用CRF模式
command = command.addOption('-row-mt', '1'); // 多线程编码
command = command.addOption('-f', 'webm');
// 优化WEBM编码参数
command = command.addOption('-deadline', 'good');
command = command.addOption('-cpu-used', '1');
break;
case 'mkv':
command = command.videoCodec('libx264').audioCodec('aac');
command = command.addOption('-preset', 'medium');
command = command.addOption('-crf', '23');
command = command.addOption('-f', 'matroska');
break;
case 'flv':
command = command.videoCodec('libx264').audioCodec('aac');
command = command.addOption('-preset', 'medium');
command = command.addOption('-crf', '25'); // FLV使用稍低质量
command = command.addOption('-f', 'flv');
break;
case 'wmv':
command = command.videoCodec('libx264').audioCodec('aac');
command = command.addOption('-preset', 'medium');
command = command.addOption('-crf', '25');
command = command.addOption('-f', 'asf'); // WMV使用ASF容器
// 修复WMV时长信息问题的关键参数
command = command.addOption('-avoid_negative_ts', 'make_zero');
command = command.addOption('-fflags', '+genpts+igndts');
command = command.addOption('-use_wallclock_as_timestamps', '1');
// 确保ASF容器正确写入时长信息
command = command.addOption('-metadata', 'title=""');
break;
case 'm4v':
command = command.videoCodec('libx264').audioCodec('aac');
command = command.addOption('-preset', 'medium');
command = command.addOption('-crf', '23');
// 修复M4V格式的关键参数
command = command.addOption('-f', 'mp4'); // M4V使用MP4容器
command = command.addOption('-movflags', '+faststart+frag_keyframe+empty_moov');
command = command.addOption('-brand', 'M4V '); // 设置M4V品牌标识
command = command.addOption('-pix_fmt', 'yuv420p');
command = command.addOption('-profile:v', 'high');
command = command.addOption('-level', '4.0');
// 确保moov atom正确写入
command = command.addOption('-write_tmcd', '0');
break;
default:
// 默认使用H.264和AAC
command = command.videoCodec('libx264').audioCodec('aac');
command = command.addOption('-preset', 'medium');
command = command.addOption('-crf', '23');
}
return command;
}
/**
* 检查格式是否使用CRF模式
*/
private usesCRF(format: string): boolean {
const crfFormats = ['mp4', 'avi', 'mov', 'webm', 'mkv', 'flv', 'wmv', 'm4v'];
return crfFormats.includes(format.toLowerCase());
}
/**
* 应用质量预设
*/
private applyQualityPreset(command: ffmpeg.FfmpegCommand, quality: string): ffmpeg.FfmpegCommand {
const presets = this.getQualityPresets();
const preset = presets[quality];
if (preset) {
// 对于使用CRF的格式，调整CRF值
if (preset.videoBitrate) {
const crf = this.bitrateToQuality(preset.videoBitrate);
command = command.addOption('-crf', crf.toString());
}
if (preset.audioBitrate) {
command = command.audioBitrate(preset.audioBitrate);
}
}
return command;
}
/**
* 将码率转换为质量参数
*/
private bitrateToQuality(bitrate: number): number {
// 码率越高，CRF值越低（质量越好）
if (bitrate >= 8000) return 18; // ultra quality
if (bitrate >= 5000) return 21; // high quality
if (bitrate >= 2500) return 23; // medium quality
return 25; // low quality
}
/**
* 获取质量预设
*/
private getQualityPresets(): Record<string, { videoBitrate?: number; audioBitrate?: number }> {
return {
low: {
videoBitrate: 1000, // 提高最低质量
audioBitrate: 96
},
medium: {
videoBitrate: 2500, // 提高中等质量
audioBitrate: 128
},
high: {
videoBitrate: 5000, // 提高高质量
audioBitrate: 192
},
ultra: {
videoBitrate: 8000, // 提高超高质量
audioBitrate: 320
}
};
}
/**
* 解析帧率字符串
*/
private parseFrameRate(frameRateStr: string | undefined): number {
if (!frameRateStr) return 0;
if (frameRateStr.includes('/')) {
const [num, den] = frameRateStr.split('/').map(Number);
return den ? Math.round((num / den) * 100) / 100 : 0;
}
return parseFloat(frameRateStr) || 0;
}
/**
* 验证输出文件完整性
*/
private async validateOutputFile(filePath: string): Promise<void> {
try {
// 检查文件是否存在
await fs.access(filePath);
// 检查文件大小
const stats = await fs.stat(filePath);
if (stats.size === 0) {
throw new Error('输出文件为空');
}
// 尝试获取视频信息来验证文件完整性
await this.getVideoInfo(filePath);
} catch (error: any) {
throw new Error(`文件验证失败: ${error.message}`);
}
}
/**
* 生成任务ID
*/
private generateTaskId(): string {
return `task_${Date.now()}_${Math.random().toString(36).substr(2, 9)}`;
}
}