我在 Rails 应用程序中运行 ffmpeg 命令将音频文件转换为 mp3:
# Convert to MP3
conversion_result = `ffmpeg -i "#{Refile::cache.directory}/#{self.file.id}" -f mp3 "#{_path_to_mp3}" 2>&1`
转换后的示例conversion_result
如下:
"ffmpeg 版本 N-74748-gbaeb8f5 版权所有 (c) 2000-2015 FFmpeg 开发人员\n 使用 gcc 4.8 (Ubuntu 4.8.4-2ubuntu1~14.04) 构建\n 配置:--extra-libs=-ldl --prefix= /opt/ffmpeg --enable-avresample --disable-debug --enable-nonfree --enable-gpl --enable-version3 --enable-libopencore-amrnb --enable-libopencore-amrwb --disable-decoder=amrnb --disable-decoder=amrwb --enable-libpulse --enable-libdcadec --enable-libfreetype --enable-libx264 --enable-libx265 --enable-libfdk-aac --enable-libvorbis --enable-libmp3lame - -enable-libopus --enable-libvpx --enable-libspeex --enable-libass --enable-avisynth --enable-libsoxr --enable-libxvid --enable-libvo-aacenc --enable-libvidstab\n libavutil 54 . 31.100 / 54. 31.100\n libavcodec 56. 59.100 / 56. 59.100\n libavformat 56. 40.101 / 56. 40.101\n libavdevice 56. 4.100 / 56. 4.100\n libavfilter 5. 40.100 / 5. 40.100\n libavresample 2. 1. 0 / 2. 1. 0\n libswscale 3. 1.101 / 3. 1.101\n libswresample 1. 2.101 / 1. 2.101\n libpostproc 53. 3.100 / 53. 3.100\ nInput #0, mov,mp4,m4a,3gp,3g2,mj2, from '../mey_attachments/cache/25888dc028deaabaee4d4de19d4726573860dbce0b907131e9919d294113':\n 元数据:\n major_brand : 3gp4\n minor_version : 0\np_brand 创建时间兼容: 2015-09-01 16:34:01\n 持续时间: 00:00:08.57, 开始: 0.000000, 比特率: 426 kb/s\n 流isom3gp4\n creation_time : 2015-09-01 16:34:01\n 持续时间: 00:00:08.57, 开始: 0.000000, 比特率: 426 kb/s\n 流isom3gp4\n creation_time : 2015-09-01 16:34:01\n 持续时间: 00:00:08.57, 开始: 0.000000, 比特率: 426 kb/s\n 流
0:0(eng): 音频: aac (LC) (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 48 kb/s (默认)\n 元数据:\n creation_time : 2015-09-01 16:34: 01\n
handler_name : SoundHandle\nOutput #0, mp3, to '/tmp/Voice00045.mp3':\n Metadata:\n major_brand : 3gp4\n minor_version : 0\n compatible_brands: isom3gp4\n TSSE : Lavf56.40.101\n Stream # 0:0(eng):音频:mp3 (libmp3lame)、44100 Hz、单声道、fltp(默认)\n 元数据:\n creation_time:2015-09-01 16:34:01\n handler_name:SoundHandle\n 编码器: Lavc56.59.100 libmp3lame\n流映射:\n Stream #0:0 -> #0:0 (aac (native) -> mp3 (libmp3lame))\n按 [q] 停止,[?] 寻求帮助\nsize= 67kB时间=00:00:08.56 比特率= 64.5kbits/s \n视频:0kB 音频:67kB 字幕:0kB 其他流:0kB 全局标题:0kB 复用开销:0.465427%\n"
命令执行后如何确保转换成功?