如果大家留意网络上一些无损音质音频文件的话，都离不开ape、flac、wav几种，mp3格式的有时候也有高音质的文件，特别是比特率达到320K、采样率48000的音频音质，都算是无损或是接近无损的音质了。
我们检测这些无损音质音频文件的方法是使用ffmpeg里的媒体检测模块ffprobe.exe，在下载或编译ffmpeg的时候，bin目录下会生成三个程序，1、是ffmpeg.exe，这个是编解码程序，2、是ffprobe.exe，这个是媒体检测程序，3、ffplaye.exe,这是媒体播放程序。
D:\ffmpeg\bin\ffprobe.exe -help
#帮助信息 查询ffprobe.exe所有用法首先我们来看一看一个ape格式的文件的检测信息。
D:\ffmpeg\bin\ffprobe.exe -of json -show_format -show_streams D:\yisheng.ape
#使用json显示所返回的文件信息
#-show_format、-show_streams可以搜索相关注释
Input #0, ape, from 'D:\yisheng.ape':
Metadata:
Album : 齊天周大聖之西遊雙記
Album artist : Various
Artist : 卢冠廷
COMMENT : 163 key(Don't modify):6YURAByiRHQ6CI5tvtxzQg==
Genre : Soundtrack
Title : 一生所爱
Track : 6/11
Year : 1999
Duration: 00:04:33.67, start: 0.000000, bitrate: 719 kb/s
Stream #0:0: Audio: ape (APE / 0x20455041), 44100 Hz, stereo, s16p
"streams": [
{
"index": 0,
"codec_name": "ape",
"codec_long_name": "Monkey's Audio",
"codec_type": "audio",
"codec_time_base": "1/44100",
"codec_tag_string": "APE ",
"codec_tag": "0x20455041",
"sample_fmt": "s16p",
"sample_rate": "44100",
"channels": 2,
"channel_layout": "stereo",
"bits_per_sample": 0,
"r_frame_rate": "0/0",
"avg_frame_rate": "0/0",
"time_base": "1/44100",
"start_pts": 0,
"start_time": "0.000000",
"duration_ts": 12068700,
"duration": "273.666667",
"nb_frames": "164",
"disposition": {
"default": 0,
"dub": 0,
"original": 0,
"comment": 0,
"lyrics": 0,
"karaoke": 0,
"forced": 0,
"hearing_impaired": 0,
"visual_impaired": 0,
"clean_effects": 0,
"attached_pic": 0,
"timed_thumbnails": 0
}
}
],
"format": {
"filename": "D:\\yisheng.ape",
"nb_streams": 1,
"nb_programs": 0,
"format_name": "ape",
"format_long_name": "Monkey's Audio",
"start_time": "0.000000",
"duration": "273.666667",
"size": "24617763",
"bit_rate": "719642",
"probe_score": 100,
"tags": {
"Album": "榻婂ぉ鍛ㄥぇ鑱栦箣瑗块亰闆欒",
"Album artist": "Various",
"Artist": "鍗㈠啝寤?,
"COMMENT": "163 key(Don't modify):6YURAByiRHQ6CI5tvtxzQg==",
"Genre": "Soundtrack",
"Title": "涓€鐢熸墍鐖?,
"Track": "6/11",
"Year": "1999"
}
}
}
PS D:\>我们可以看到，音频采样率是44100hz，这个就是无损音质的标准了。
D:\ffmpeg\bin\ffprobe.exe -of json -show_format -show_streams D:\tingwen.flac
#检测flac格式的文件
Input #0, flac, from 'D:\tingwen.flac':
Metadata:
ALBUM : 听闻远方有你
ARTIST : 刘艺 雯
TITLE : 听闻远方有你
Duration: 00:04:19.47, start: 0.000000, bitrate: 942 kb/s
Stream #0:0: Audio: flac, 44100 Hz, stereo, s16
Stream #0:1: Video: mjpeg (Baseline), yuvj444p(pc, bt470bg/unknown/unknown), 800x800 [SAR 72:72 DAR 1:1], 90k tbr, 9
0k tbn, 90k tbc (attached pic)
Metadata:
comment : Cover (front)
"streams": [
{
"index": 0,
"codec_name": "flac",
"codec_long_name": "FLAC (Free Lossless Audio Codec)",
"codec_type": "audio",
"codec_time_base": "1/44100",
"codec_tag_string": "[0][0][0][0]",
"codec_tag": "0x0000",
"sample_fmt": "s16",
"sample_rate": "44100",
"channels": 2,
"channel_layout": "stereo",
"bits_per_sample": 0,
"r_frame_rate": "0/0",
"avg_frame_rate": "0/0",
"time_base": "1/44100",
"start_pts": 0,
"start_time": "0.000000",
"duration_ts": 11442513,
"duration": "259.467415",
"bits_per_raw_sample": "16",
"disposition": {
"default": 0,
"dub": 0,
"original": 0,
"comment": 0,
"lyrics": 0,
"karaoke": 0,
"forced": 0,
"hearing_impaired": 0,
"visual_impaired": 0,
"clean_effects": 0,
"attached_pic": 0,
"timed_thumbnails": 0
}
},
{
"index": 1,
"codec_name": "mjpeg",
"codec_long_name": "Motion JPEG",
"profile": "Baseline",
"codec_type": "video",
"codec_time_base": "0/1",
"codec_tag_string": "[0][0][0][0]",
"codec_tag": "0x0000",
"width": 800,
"height": 800,
"coded_width": 800,
"coded_height": 800,
"closed_captions": 0,
"has_b_frames": 0,
"sample_aspect_ratio": "1:1",
"display_aspect_ratio": "1:1",
"pix_fmt": "yuvj444p",
"level": -99,
"color_range": "pc",
"color_space": "bt470bg",
"chroma_location": "center",
"refs": 1,
"r_frame_rate": "90000/1",
"avg_frame_rate": "0/0",
"time_base": "1/90000",
"start_pts": 0,
"start_time": "0.000000",
"duration_ts": 23352067,
"duration": "259.467411",
"bits_per_raw_sample": "8",
"disposition": {
"default": 0,
"dub": 0,
"original": 0,
"comment": 0,
"lyrics": 0,
"karaoke": 0,
"forced": 0,
"hearing_impaired": 0,
"visual_impaired": 0,
"clean_effects": 0,
"attached_pic": 1,
"timed_thumbnails": 0
},
"tags": {
"comment": "Cover (front)"
}
}
],
"format": {
"filename": "D:\\tingwen.flac",
"nb_streams": 2,
"nb_programs": 0,
"format_name": "flac",
"format_long_name": "raw FLAC",
"start_time": "0.000000",
"duration": "259.467415",
"size": "30578900",
"bit_rate": "942820",
"probe_score": 100,
"tags": {
"ALBUM": "鍚椈杩滄柟鏈変綘",
"ARTIST": "鍒樿壓 闆?,
"TITLE": "鍚椈杩滄柟鏈変綘"
}
}
}
PS D:\>
上边这个flac格式的文件的采样率也是44100hz
接下来我们看一个高音质的mp3文件的检测信息，这个文件是从某云听歌平台上下载的无损音质文件，但是它却是mp3格式的。
D:\ffmpeg\bin\ffprobe.exe -of json -show_format -show_streams D:\guxiangfengjing.mp3
Input #0, mp3, from 'D:\guxiangfengjing.mp3':
Metadata:
genre : Newage
encoder : Lavf56.4.101
comment : 163 key(Don't modify):L64FU3W4YxX3ZFTmbZ+8/VcZXal+0oHC6/7jrIQD5RCm3ok4oJqz1rmYIq3fPgZr7oVhFxjFHEpf
Xsx1Vo0FkUTxYwLVHUgpQj0RcSPVDd8icyi9gEvyIV3kemBc/XTTMp/r0k9XpFbMELrX1Rq06MZN6OV9ZHzm13DArU7sD/xtUX433smIIMoYEoS1xhdC/6IB
tfiULFAi9LmBRvmyaT4giJqztMUu+JHGWPVEO
album : Kidou 木道
title : 故郷の原风景
artist : 宗次郎
disc : 1
track : 1
date : 1997
Duration: 00:04:42.75, start: 0.025056, bitrate: 338 kb/s
Stream #0:0: Audio: mp3, 44100 Hz, stereo, fltp, 320 kb/s
Stream #0:1: Video: mjpeg (Baseline), yuvj444p(pc, bt470bg/unknown/unknown), 640x640 [SAR 72:72 DAR 1:1], 90k tbr, 9
0k tbn, 90k tbc (attached pic)
Metadata:
comment : Media (e.g. label side of CD)
"streams": [
{
"index": 0,
"codec_name": "mp3",
"codec_long_name": "MP3 (MPEG audio layer 3)",
"codec_type": "audio",
"codec_time_base": "1/44100",
"codec_tag_string": "[0][0][0][0]",
"codec_tag": "0x0000",
"sample_fmt": "fltp",
"sample_rate": "44100",
"channels": 2,
"channel_layout": "stereo",
"bits_per_sample": 0,
"r_frame_rate": "0/0",
"avg_frame_rate": "0/0",
"time_base": "1/14112000",
"start_pts": 353600,
"start_time": "0.025057",
"duration_ts": 3990159360,
"duration": "282.749388",
"bit_rate": "320000",
"disposition": {
"default": 0,
"dub": 0,
"original": 0,
"comment": 0,
"lyrics": 0,
"karaoke": 0,
"forced": 0,
"hearing_impaired": 0,
"visual_impaired": 0,
"clean_effects": 0,
"attached_pic": 0,
"timed_thumbnails": 0
}
},
{
"index": 1,
"codec_name": "mjpeg",
"codec_long_name": "Motion JPEG",
"profile": "Baseline",
"codec_type": "video",
"codec_time_base": "0/1",
"codec_tag_string": "[0][0][0][0]",
"codec_tag": "0x0000",
"width": 640,
"height": 640,
"coded_width": 640,
"coded_height": 640,
"closed_captions": 0,
"has_b_frames": 0,
"sample_aspect_ratio": "1:1",
"display_aspect_ratio": "1:1",
"pix_fmt": "yuvj444p",
"level": -99,
"color_range": "pc",
"color_space": "bt470bg",
"chroma_location": "center",
"refs": 1,
"r_frame_rate": "90000/1",
"avg_frame_rate": "0/0",
"time_base": "1/90000",
"start_pts": 2255,
"start_time": "0.025056",
"duration_ts": 25447445,
"duration": "282.749389",
"bits_per_raw_sample": "8",
"disposition": {
"default": 0,
"dub": 0,
"original": 0,
"comment": 0,
"lyrics": 0,
"karaoke": 0,
"forced": 0,
"hearing_impaired": 0,
"visual_impaired": 0,
"clean_effects": 0,
"attached_pic": 1,
"timed_thumbnails": 0
},
"tags": {
"comment": "Media (e.g. label side of CD)"
}
}
],
"format": {
"filename": "D:\\guxiangfengjing.mp3",
"nb_streams": 2,
"nb_programs": 0,
"format_name": "mp3",
"format_long_name": "MP2/3 (MPEG audio layer 2/3)",
"start_time": "0.025056",
"duration": "282.749388",
"size": "11976986",
"bit_rate": "338872",
"probe_score": 51,
"tags": {
"genre": "Newage",
"encoder": "Lavf56.4.101",
"comment": "163 key(Don't modify):L64FU3W4YxX3ZFTmbZ+8/VcZXal+0oHC6/7jrIQD5RCm3ok4oJqz1rmYIq3fPgZr7oVhFxjFHE
pfXsx1Vo0FkUTxYwLVHUgpQj0RcSPVDd8icyi9gEvyIV3kemBc/XTTMp/r0k9XpFbMELrX1Rq06MZN6OV9ZHzm13DArU7sD/xtUX433smIIMoYEoS1xhdC/6
IBtfiULFAi9LmBRvmyaT4giJqztMUu+JHGWPVEOCH9toFWVNES9chRg9hR0047PwDY7mRGbuJGvDRn2LnmJsy9brN3O9OG31cR8m6nc0d+nH6kVEqHdxBLhf
XW3pIEzl9NWazcbywoS+OyWdjG9KojjAdCuWnMdlKS7I5o5rCwv8bRpNMntguTnwEX99GznRe4XaIJkzvoB7cutJHHltHE5ZtUm/TCVCsrzX9phCuAp+hXNC
9B89E5O/pyVBkI95pUv+gIqUUfxcePdBzyWZS7tZh/+DR+8/ZGhkwKPMbl1OcrMT3tzvhSf3GCcF/u7b8cQdI8quSJAZ02VcS4zA==",
"album": "Kidou 鏈ㄩ亾",
"title": "鏁呴兎銇師椋庢櫙",
"artist": "瀹楁閮?,
"disc": "1",
"track": "1",
"date": "1997"
}
}
}
PS D:\>
如果大家仔细看，可以看出来里边的一些信息是符合我们无损音质文件的特征的，采样率44100、比特率320k等。
下边这个wav文件是华为Mate手机的电话录音机录制的，但是它也是符合无损音质的一些特征的。
所以，一般我们分析音频文件是否是无损音质的时候，不光是需要分辨它的文件格式，我们还需要分析它的编解码信息和一些比特率、采样率等。
