FFMPEG 信息查询

一、问题描述

　　最近测试反馈一个隐私模式的问题，主播端启用隐私模式之后，在观看端发现画面转菊花并且还有回跳的现象

二、问题分析：

　　从网上下载了直播的视频文件，进行了一下分析，发现视频长度和音频长度不匹配，视频只有2分钟，音频有8分钟

　　怀疑是视频编码失败导致，因为没有log，不能够确认当时的情况，现在将排查的一些过程记录下

　　

LUNLI-MC1:隐私模式问题排查 lunli$ ffprobe playlist-playlist.mp4 
ffprobe version 3.4 Copyright (c) 2007-2017 the FFmpeg developers
  built with Apple LLVM version 9.0.0 (clang-900.0.38)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/3.4 --enable-shared --enable-pthreads --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-gpl --enable-ffplay --enable-libmp3lame --enable-libx264 --enable-libxvid --enable-opencl --enable-videotoolbox --disable-lzma
  libavutil      55. 78.100 / 55. 78.100
  libavcodec     57.107.100 / 57.107.100
  libavformat    57. 83.100 / 57. 83.100
  libavdevice    57. 10.100 / 57. 10.100
  libavfilter     6.107.100 /  6.107.100
  libavresample   3.  7.  0 /  3.  7.  0
  libswscale      4.  8.100 /  4.  8.100
  libswresample   2.  9.100 /  2.  9.100
  libpostproc    54.  7.100 / 54.  7.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'playlist-playlist.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf57.83.100
  Duration: 00:07:30.64, start: 0.000000, bitrate: 156 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuvj420p(pc), 1136x640, 395 kb/s, 21.30 fps, 90k tbr, 90k tbn, 180k tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 9 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
LUNLI-MC1:隐私模式问题排查 lunli$ mp4box -info playlist-playlist.mp4 
* Movie Info *
	Timescale 1000 - 2 tracks
	Computed Duration 00:07:30.644 - Indicated Duration 00:07:30.635
	Fragmented File: no
	File Brand isom - version 512
		Compatible brands: isom iso2 avc1 mp41
	Created: UNKNOWN DATE	Modified: UNKNOWN DATE
File has no MPEG4 IOD/OD

iTunes Info:
	Encoder Software: Lavf57.83.100
1 UDTA types: meta (1) 

Track # 1 Info - TrackID 1 - TimeScale 90000
Media Duration 00:02:41.526 - Indicated Duration 00:02:41.526
Track has 1 edit lists: track duration is 00:02:41.527
Media Info: Language "Undetermined (und)" - Type "vide:avc1" - 3441 samples
Visual Track layout: x=0 y=0 width=1136 height=640
MPEG-4 Config: Visual Stream - ObjectTypeIndication 0x21
AVC/H264 Video - Visual Size 1136 x 640
	AVC Info: 1 SPS - 1 PPS - Profile High @ Level 3.1
	NAL Unit length bits: 32
	Chroma format YUV 4:2:0 - Luma bit depth 8 - chroma bit depth 8
	SPS#1 hash: E00BB071FEBC7AB23BDF361BA3FDC361F6B6CB76
	PPS#1 hash: 846C70462484FB50AF3D7777307A8158D2D5AB5E
Self-synchronized
	RFC6381 Codec Parameters: avc1.64001F
	Average GOP length: 66 samples

Track # 2 Info - TrackID 2 - TimeScale 44100
Media Duration 00:07:30.634 - Indicated Duration 00:07:30.634
Track has 2 edit lists: track duration is 00:07:30.644
Media Info: Language "Undetermined (und)" - Type "soun:mp4a" - 19441 samples
MPEG-4 Config: Audio Stream - ObjectTypeIndication 0x40
MPEG-4 Audio AAC LC - 1 Channel(s) - SampleRate 44100
Synchronized on stream 1
	RFC6381 Codec Parameters: mp4a.40.2
Alternate Group ID 1
	All samples are sync