【发布时间】:2020-12-05 03:49:14
【问题描述】:
我已经下载了一个 [short media][1] 我打算转换然后我将使用结果作为基础来练习和测试我以后学习或使用的任何和所有 FFMPEG 命令。
该视频似乎有一个未知的无效流,无论我试图丢弃它的一切,它都不会消失。当我稍后尝试使用它时,我遇到了各种问题,例如缺少编解码器或没有流,这不是这里的重点,而是我顽固地删除我无法处理的事情的原因。
以下探测在最后一行打印黄色警告。
> ffprobe -hide_banner -show_streams Movie_Countdown-youtube_I1vMKZ1kvg0.mov
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'Movie_Countdown-youtube_I1vMKZ1kvg0.mov':
Metadata:
major_brand : qt
minor_version : 537199360
compatible_brands: qt
creation_time : 2015-05-20T13:45:55.000000Z
Duration: 00:00:10.00, start: 0.000000, bitrate: 11474 kb/s
Stream #0:0(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, bt709), 1920x1080, 9930 kb/s, SAR 1:1 DAR 16:9, 25 fps, 25 tbr, 25 tbn, 50 tbc (default)
Metadata:
creation_time : 2015-05-20T13:45:55.000000Z
handler_name : Apple Video Media Handler
encoder : H.264
timecode : 00:00:00:00
Stream #0:1(eng): Audio: pcm_s16le (sowt / 0x74776F73), 48000 Hz, stereo, s16, 1536 kb/s (default)
Metadata:
creation_time : 2015-05-20T13:45:56.000000Z
handler_name : Apple Sound Media Handler
timecode : 00:00:00:00
Stream #0:2(eng): Data: none (tmcd / 0x64636D74), 0 kb/s (default)
Metadata:
creation_time : 2015-05-20T13:46:11.000000Z
handler_name : Time Code Media Handler
timecode : 00:00:00:00
Unsupported codec with id 0 for input stream 2
在流输出下方。我拆分了文本,因此您无需在中间搜索即可看到警告。
[STREAM]
index=0
codec_name=h264
codec_long_name=H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10
profile=Main
codec_type=video
codec_time_base=1/50
codec_tag_string=avc1
codec_tag=0x31637661
width=1920
height=1080
coded_width=1920
coded_height=1088
closed_captions=0
has_b_frames=0
sample_aspect_ratio=1:1
display_aspect_ratio=16:9
pix_fmt=yuv420p
level=40
color_range=tv
color_space=bt709
color_transfer=bt709
color_primaries=bt709
chroma_location=left
field_order=unknown
timecode=N/A
refs=1
is_avc=true
nal_length_size=4
id=N/A
r_frame_rate=25/1
avg_frame_rate=25/1
time_base=1/25
start_pts=0
start_time=0.000000
duration_ts=250
duration=10.000000
bit_rate=9930739
max_bit_rate=N/A
bits_per_raw_sample=8
nb_frames=250
nb_read_frames=N/A
nb_read_packets=N/A
DISPOSITION:default=1
DISPOSITION:dub=0
DISPOSITION:original=0
DISPOSITION:comment=0
DISPOSITION:lyrics=0
DISPOSITION:karaoke=0
DISPOSITION:forced=0
DISPOSITION:hearing_impaired=0
DISPOSITION:visual_impaired=0
DISPOSITION:clean_effects=0
DISPOSITION:attached_pic=0
DISPOSITION:timed_thumbnails=0
TAG:creation_time=2015-05-20T13:45:55.000000Z
TAG:language=eng
TAG:handler_name=Apple Video Media Handler
TAG:encoder=H.264
TAG:timecode=00:00:00:00
[/STREAM]
[STREAM]
index=1
codec_name=pcm_s16le
codec_long_name=PCM signed 16-bit little-endian
profile=unknown
codec_type=audio
codec_time_base=1/48000
codec_tag_string=sowt
codec_tag=0x74776f73
sample_fmt=s16
sample_rate=48000
channels=2
channel_layout=stereo
bits_per_sample=16
id=N/A
r_frame_rate=0/0
avg_frame_rate=0/0
time_base=1/48000
start_pts=0
start_time=0.000000
duration_ts=480000
duration=10.000000
bit_rate=1536000
max_bit_rate=N/A
bits_per_raw_sample=N/A
nb_frames=480000
nb_read_frames=N/A
nb_read_packets=N/A
DISPOSITION:default=1
DISPOSITION:dub=0
DISPOSITION:original=0
DISPOSITION:comment=0
DISPOSITION:lyrics=0
DISPOSITION:karaoke=0
DISPOSITION:forced=0
DISPOSITION:hearing_impaired=0
DISPOSITION:visual_impaired=0
DISPOSITION:clean_effects=0
DISPOSITION:attached_pic=0
DISPOSITION:timed_thumbnails=0
TAG:creation_time=2015-05-20T13:45:56.000000Z
TAG:language=eng
TAG:handler_name=Apple Sound Media Handler
TAG:timecode=00:00:00:00
[/STREAM]
[STREAM]
index=2
codec_name=unknown
codec_long_name=unknown
profile=unknown
codec_type=data
codec_tag_string=tmcd
codec_tag=0x64636d74
id=N/A
r_frame_rate=0/0
avg_frame_rate=25/1
time_base=1/25
start_pts=0
start_time=0.000000
duration_ts=250
duration=10.000000
bit_rate=3
max_bit_rate=N/A
bits_per_raw_sample=N/A
nb_frames=1
nb_read_frames=N/A
nb_read_packets=N/A
DISPOSITION:default=1
DISPOSITION:dub=0
DISPOSITION:original=0
DISPOSITION:comment=0
DISPOSITION:lyrics=0
DISPOSITION:karaoke=0
DISPOSITION:forced=0
DISPOSITION:hearing_impaired=0
DISPOSITION:visual_impaired=0
DISPOSITION:clean_effects=0
DISPOSITION:attached_pic=0
DISPOSITION:timed_thumbnails=0
TAG:creation_time=2015-05-20T13:46:11.000000Z
TAG:language=eng
TAG:handler_name=Time Code Media Handler
TAG:timecode=00:00:00:00
[/STREAM]
我将其缩小并重新编码以供初学者使用,我尝试使用-dn 丢弃数据流,但我将在最后提到的其他方法失败。
到目前为止的输出表明丢弃应该是可行的,因为替代数据是 0kB 并且没有列出流 2。
> ffmpeg -hide_banner -dn -i C:\Users\admin-dix\Downloads\Movie_Countdown-youtube_I1vMKZ1kvg0.mov -vf "scale=h=450:w=800" -f mp4 -c:a aac -c:v libx264 mov_countdown.mp4
Output #0, mp4, to 'mov_countdown.mp4':
Metadata:
major_brand : qt
minor_version : 537199360
compatible_brands: qt
encoder : Lavf58.45.100
Stream #0:0(eng): Video: h264 (libx264) (avc1 / 0x31637661), yuv420p(progressive), 800x450 [SAR 1:1 DAR 16:9], q=-1--1, 0.04 fps, 12800 tbn, 25 tbc (default)
Metadata:
creation_time : 2015-05-20T13:45:55.000000Z
handler_name : Apple Video Media Handler
timecode : 00:00:00:00
encoder : Lavc58.91.100 libx264
Side data:
cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: N/A
Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
Metadata:
creation_time : 2015-05-20T13:45:56.000000Z
handler_name : Apple Sound Media Handler
timecode : 00:00:00:00
encoder : Lavc58.91.100 aac
frame= 250 fps= 43 q=-1.0 Lsize= 342kB time=00:00:10.00 bitrate= 280.1kbits/s speed= 1.7x
video:175kB audio:159kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 2.710857%
然后ffprobe不同意,还有流和警告。
ffprobe mov_countdown.mp4
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'mov_countdown.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.45.100
Duration: 00:00:10.02, start: 0.000000, bitrate: 279 kb/s
Stream #0:0(eng): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 800x450 [SAR 1:1 DAR 16:9], 142 kb/s, 25 fps, 25 tbr, 12800 tbn, 50 tbc (default)
Metadata:
handler_name : Apple Video Media Handler
timecode : 00:00:00:00
Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 129 kb/s (default)
Metadata:
handler_name : Apple Sound Media Handler
Stream #0:2(eng): Data: none (tmcd / 0x64636D74), 0 kb/s
Metadata:
handler_name : Apple Video Media Handler
timecode : 00:00:00:00
Unsupported codec with id 0 for input stream 2
我根据this answer-map 0:d 尝试了负映射,但失败了。我不理解 -discard 选项,因为 ffmpeg 文档引用了 -vn,-an,-dn 条目,因为它没有指定流。
为什么要这样做,我怎样才能删除我不知道并且不想在以后的测试中关心的流?
[1]:清洁复古电影倒计时 - 来自 Philippe Moesch 的 YouTube https://www.youtube.com/watch?v=I1vMKZ1kvg0
【问题讨论】:
标签: ffmpeg