![问题解决了。](https://linux22.com/image/1323003/%E9%97%AE%E9%A2%98%E8%A7%A3%E5%86%B3%E4%BA%86%E3%80%82.png)
我正在尝试使用以下命令将图像序列(frame0001.png
,,frame0002.png
..., )编码为 x264 视频:frame0160.png
ffmpeg -i frame%04d.png -sameq -r 24 out.mp4
编码后,它说drop=5
视频中确实有明显的“跳跃”。
似乎其他人也遇到了类似的问题,但对我来说接受的答案不是很有用,因为我不希望出现丢帧的情况。
命令中缺少开关吗?还是我做错了什么?
编辑:添加控制台输出:
ffmpeg version N-42347-g299387e Copyright (c) 2000-2012 the FFmpeg developers
built on Jul 8 2012 15:46:39 with gcc 4.7.1
configuration: --disable-static --enable-shared --enable-gpl --enable-version3
--disable-w32threads --enable-runtime-cpudetect --enable-avisynth --enable-bzli
b --enable-frei0r --enable-libass --enable-libcelt --enable-libopencore-amrnb --
enable-libopencore-amrwb --enable-libfreetype --enable-libgsm --enable-libmp3lam
e --enable-libnut --enable-libopenjpeg --enable-librtmp --enable-libschroedinger
--enable-libspeex --enable-libtheora --enable-libutvideo --enable-libvo-aacenc
--enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libx264 --en
able-libxavs --enable-libxvid --enable-zlib
libavutil 51. 64.100 / 51. 64.100
libavcodec 54. 33.100 / 54. 33.100
libavformat 54. 15.102 / 54. 15.102
libavdevice 54. 1.100 / 54. 1.100
libavfilter 3. 1.100 / 3. 1.100
libswscale 2. 1.100 / 2. 1.100
libswresample 0. 15.100 / 0. 15.100
libpostproc 52. 0.100 / 52. 0.100
Input #0, image2, from 'frame%04d.png':
Duration: 00:00:06.40, start: 0.000000, bitrate: N/A
Stream #0:0: Video: png, rgb24, 1920x1080, 25 fps, 25 tbr, 25 tbn, 25 tbc
[graph 0 input from stream 0:0 @ 01cd1f60] w:1920 h:1080 pixfmt:rgb24 tb:1/25 fr
:25/1 sar:0/1 sws_param:flags=2
[output stream 0:0 @ 01cd2220] No opaque field provided
[auto-inserted scaler 0 @ 01cd3540] w:1920 h:1080 fmt:rgb24 sar:0/1 -> w:1920 h:
1080 fmt:yuv420p sar:0/1 flags:0x4
[libx264 @ 01cd0dc0] using cpu capabilities: MMX2 SSE2Fast SSSE3 Cache64
[libx264 @ 01cd0dc0] profile High, level 4.0
[libx264 @ 01cd0dc0] 264 - core 125 r2200 999b753 - H.264/MPEG-4 AVC codec - Cop
yleft 2003-2012 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deb
lock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 m
e_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chro
ma_qp_offset=-2 threads=6 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 i
nterlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1
b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=24 scenec
ut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=
0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to 'out.mp4':
Metadata:
encoder : Lavf54.15.102
Stream #0:0: Video: h264 ([33][0][0][0] / 0x0021), yuv420p, 1920x1080, q=-1-
-1, 24 tbn, 24 tbc
Stream mapping:
Stream #0:0 -> #0:0 (png -> libx264)
Press [q] to stop, [?] for help
frame= 8 fps=0.0 q=0.0 size= 0kB time=00:00:00.00 bitrate= 0.0kbits/s
frame= 15 fps= 15 q=0.0 size= 0kB time=00:00:00.00 bitrate= 0.0kbits/s
frame= 22 fps= 14 q=0.0 size= 0kB time=00:00:00.00 bitrate= 0.0kbits/s
frame= 29 fps= 14 q=0.0 size= 0kB time=00:00:00.00 bitrate= 0.0kbits/s
frame= 36 fps= 14 q=0.0 size= 0kB time=00:00:00.00 bitrate= 0.0kbits/s
frame= 43 fps= 14 q=0.0 size= 0kB time=00:00:00.00 bitrate= 0.0kbits/s
frame= 47 fps= 11 q=0.0 size= 0kB time=00:00:00.00 bitrate= 0.0kbits/s
frame= 53 fps= 11 q=28.0 size= 111kB time=00:00:00.04 bitrate=21735.2kbits
frame= 59 fps= 11 q=28.0 size= 268kB time=00:00:00.29 bitrate=7527.8kbits/
frame= 63 fps= 10 q=28.0 size= 375kB time=00:00:00.45 bitrate=6708.1kbits/
frame= 69 fps= 10 q=28.0 size= 538kB time=00:00:00.70 bitrate=6219.6kbits/
frame= 74 fps= 10 q=28.0 size= 675kB time=00:00:00.91 bitrate=6032.7kbits/
frame= 79 fps= 10 q=28.0 size= 802kB time=00:00:01.12 bitrate=5840.7kbits/
frame= 84 fps= 10 q=28.0 size= 922kB time=00:00:01.33 bitrate=5662.9kbits/
frame= 89 fps=9.9 q=28.0 size= 1060kB time=00:00:01.54 bitrate=5633.3kbits/
frame= 94 fps=9.9 q=28.0 size= 1186kB time=00:00:01.75 bitrate=5551.2kbits/
frame= 98 fps=9.7 q=28.0 size= 1309kB time=00:00:01.91 bitrate=5594.3kbits/
frame= 103 fps=9.7 q=28.0 size= 1436kB time=00:00:02.12 bitrate=5536.4kbits/
frame= 107 fps=9.6 q=28.0 size= 1533kB time=00:00:02.29 bitrate=5481.7kbits/
frame= 112 fps=9.5 q=28.0 size= 1654kB time=00:00:02.50 bitrate=5421.3kbits/
frame= 117 fps=9.4 q=28.0 size= 1781kB time=00:00:02.70 bitrate=5386.9kbits/
frame= 123 fps=9.4 q=28.0 size= 1925kB time=00:00:02.95 bitrate=5331.5kbits/
frame= 128 fps=9.4 q=28.0 size= 2030kB time=00:00:03.16 bitrate=5250.8kbits/
frame= 133 fps=9.4 q=28.0 size= 2210kB time=00:00:03.37 bitrate=5363.8kbits/
frame= 138 fps=9.3 q=28.0 size= 2356kB time=00:00:03.58 bitrate=5386.0kbits/
frame= 142 fps=9.3 q=28.0 size= 2465kB time=00:00:03.75 bitrate=5384.3kbits/
frame= 147 fps=9.3 q=28.0 size= 2602kB time=00:00:03.95 bitrate=5385.0kbits/
frame= 151 fps=9.2 q=28.0 size= 2706kB time=00:00:04.12 bitrate=5374.3kbits/
frame= 155 fps=9.2 q=28.0 size= 2812kB time=00:00:04.29 bitrate=5367.7kbits/
frame= 155 fps=7.0 q=28.0 Lsize= 4129kB time=00:00:06.37 bitrate=5306.4kbits
/s dup=0 drop=5
video:4128kB audio:0kB subtitle:0 global headers:0kB muxing overhead 0.035320%
[libx264 @ 01cd0dc0] frame I:2 Avg QP:21.97 size: 79850
[libx264 @ 01cd0dc0] frame P:153 Avg QP:23.43 size: 26579
[libx264 @ 01cd0dc0] mb I I16..4: 9.6% 70.5% 19.9%
[libx264 @ 01cd0dc0] mb P I16..4: 7.0% 15.3% 0.7% P16..4: 45.2% 9.1% 2.2%
0.0% 0.0% skip:20.5%
[libx264 @ 01cd0dc0] 8x8 transform intra:66.7% inter:85.7%
[libx264 @ 01cd0dc0] coded y,uvDC,uvAC intra: 38.6% 58.0% 6.0% inter: 16.2% 27.2
% 0.2%
[libx264 @ 01cd0dc0] i16 v,h,dc,p: 35% 29% 17% 19%
[libx264 @ 01cd0dc0] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 26% 21% 31% 3% 4% 5% 4%
4% 3%
[libx264 @ 01cd0dc0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 29% 19% 13% 5% 8% 9% 7%
6% 4%
[libx264 @ 01cd0dc0] i8c dc,h,v,p: 49% 23% 23% 5%
[libx264 @ 01cd0dc0] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 01cd0dc0] ref P L0: 84.5% 10.9% 3.5% 1.1%
[libx264 @ 01cd0dc0] kb/s:5235.14
答案1
问题解决了。
通过查看控制台输出,似乎输入序列的默认帧速率为 25 fps:
Input #0, image2, from 'frame%04d.png':
Duration: 00:00:06.40, start: 0.000000, bitrate: N/A
Stream #0:0: Video: png, rgb24, 1920x1080, 25 fps, 25 tbr, 25 tbn, 25 tbc
来自文档:
强制将输入文件的帧速率(仅对原始格式有效)设置为 1 fps,并将输出文件的帧速率设置为 24 fps:
ffmpeg -r 1 -i input.m2v -r 24 output.avi
因此,我需要做的只是添加另一个-r 24
:
ffmpeg
-r 24
-i frame%04d.png -r 24 out.mp4
答案2
丢帧的另一个原因是 .png 的格式不同。例如,通过 ImageMagickconvert
命令创建的 .png 通常是“颜色 RGB”,但颜色少于 256 种的 .png 会被默默优化为“颜色图”或调色板,以减小文件大小。当 ffmpeg 遇到从一个格式到另一个格式的更改时,它会开始丢帧:
Input stream #0:0 frame changed from size:1280x720 fmt:rgb24 to size:1280x720 fmt:pal8
Input stream #0:0 frame changed from size:1280x720 fmt:pal8 to size:1280x720 fmt:rgb24
为了避免丢失此类帧,convert -define png:color-type=2
。
答案3
另一个答案是错误的,正确的命令是:
ffmpeg -framerate 24 -i frame%04d.png out.mp4
-framerate 选项特定于 image2“图像序列”输入,指定图像序列的原始帧速率。请参阅:https://www.ffmpeg.org/ffmpeg-formats.html#image2-1
此选项应放置在图像序列输入之前,以应用于该输入。以正确的方式指定帧速率还可确保某些视频过滤器按预期工作。