比较好用媒体信息获取工具ffprobe
之前在项目中一直用mediainfo来获取媒体文件或流的信息，比如封装格式、音视频编码格式、码率等信息。
但实际使用中发现mediainfo输出的字段不容易被解析，而且表述方法不统一。例如，对于h264这种编码格式，mediainfo可能输出的表述为H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10；还比如，对于mp3这样的音频格式，居然会分两个字段进行描述，分别说明mpeg和layer3。所以在项目中苦于这种不确定的因素。
之前就在ffmpeg官网上看过ffprobe，不过名气被ffmpeg盖过了，没多少人使用，网上也没有什么介绍的资料。算了，自己写一点，记录一下吧。
官网说明：http://ffmpeg.org/ffprobe.html
ffprobe的编译就不说了，编译ffmpeg时控制一下configure的参数即可。
OK，下面简单使用一下。
命令行：
./ffprobe -print_format json -show_format -show_streams -i ./video/c.ts
其中：
-print_format json（以json格式输出），
-show_format（输出封装格式信息），
-show_streams（输出流信息），
-i ./video/c.ts（输入文件）
Input #0, mpegts, from './video/c.ts':
Duration: 00:00:59.67, start: 1.172511, bitrate: 919 kb/s
Program 1
Metadata:
service_name : Service01
service_provider: FFmpeg
Stream #0:0[0x100]: Video: h264 (High) ([27][0][0][0] / 0x001B), yuv420p, 640x360, 25 fps, 25 tbr, 90k tbn, 50 tbc
Stream #0:1[0x101]: Audio: aac ([15][0][0][0] / 0x000F), 44100 Hz, stereo, fltp, 103 kb/s
"streams": [
{
"index": 0,
"codec_name": "h264",
"codec_long_name": "H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10",
"profile": "High",
"codec_type": "video",
"codec_time_base": "1/50",
"codec_tag_string": "[27][0][0][0]",
"codec_tag": "0x001b",
"width": 640,
"height": 360,
"has_b_frames": 2,
"sample_aspect_ratio": "0:1",
"display_aspect_ratio": "0:1",
"pix_fmt": "yuv420p",
"level": 30,
"is_avc": "0",
"nal_length_size": "0",
"id": "0x100",
"r_frame_rate": "25/1",
"avg_frame_rate": "25/1",
"time_base": "1/90000",
"start_pts": 108000,
"start_time": "1.200000",
"duration_ts": 5367600,
"duration": "59.640000",
"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
}
},
{
"index": 1,
"codec_name": "aac",
"codec_long_name": "AAC (Advanced Audio Coding)",
"codec_type": "audio",
"codec_time_base": "1/44100",
"codec_tag_string": "[15][0][0][0]",
"codec_tag": "0x000f",
"sample_fmt": "fltp",
"sample_rate": "44100",
"channels": 2,
"bits_per_sample": 0,
"id": "0x101",
"r_frame_rate": "0/0",
"avg_frame_rate": "0/0",
"time_base": "1/90000",
"start_pts": 105526,
"start_time": "1.172511",
"duration_ts": 5340780,
"duration": "59.342000",
"bit_rate": "103359",
"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
}
}
],
"format": {
"filename": "./video/c.ts",
"nb_streams": 2,
"format_name": "mpegts",
"format_long_name": "MPEG-TS (MPEG-2 Transport Stream)",
"start_time": "1.172511",
"duration": "59.667489",
"size": "6859932",
"bit_rate": "919754"
}
}
嗯，效果还是不错的。