Sto usando FFMPEG per codificare sottotitoli in un video. Avendo letto molti post sull'approccio migliore e se usare mkv o mp4, ma non sono ancora il più saggio. Il codice seguente utilizza un file mp4. I sottotitoli sembrano essere elaborati, a giudicare dall'output, ma la dimensione 0kb sembra mostrare che nulla è effettivamente reso, e il file di output ha audio e video, ma nessun sottotitolo.
I metadati in VLC mostrano che è presente un file di sottotitoli, ma vuoto.
Ecco un esempio del mio file SRT (non mettere una riga vuota in 1 dà un errore di input msg):
1
00:00:00,000 --> 00:00:00,001
2
00:00:00,001 –-> 00:00:04,761
He drives to school every morning
3
00:00:04,761 –-> 00:00:13,061
Cause love comes slow and it goes so fast
Il mio codice da riga di comando è:
`ffmpeg -i #{inputfile} -i #{srt_file} -filter_complex "[0:v][1:s]overlay" #{outputfile} -y`
Ho anche provato:
`ffmpeg -i #{inputfile} -i #{srt_file} -c:v libx264 -preset ultrafast \
-c:s mov_text -map 0 -map 1 #{outputfile}`
E la risposta:
ffmpeg version 2.5.4 Copyright (c) 2000-2015 the FFmpeg developers
built on Feb 25 2015 15:52:19 with Apple LLVM version 6.0 (clang-600.0.54)
(based on LLVM3.5svn)
configuration: --prefix=/usr/local/Cellar/ffmpeg/2.5.4 --enable-shared --enable-pthreads
--enable-gpl --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --
host-cflags= --host-ldflags= --enable-libx264 --enable-libmp3lame --enable-libvo-aacenc
--enable-libxvid --enable-libass --enable-vda
libavutil 54. 15.100 / 54. 15.100
libavcodec 56. 13.100 / 56. 13.100
libavformat 56. 15.102 / 56. 15.102
libavdevice 56. 3.100 / 56. 3.100
libavfilter 5. 2.103 / 5. 2.103
libavresample 2. 1. 0 / 2. 1. 0
libswscale 3. 1.101 / 3. 1.101
libswresample 1. 1.100 / 1. 1.100
libpostproc 53. 3.100 / 53. 3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from
'/Users/JW/Dropbox/T10/SBRI/_code/videos_final/3rd person present tense (303).mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf56.15.102
Duration: 00:00:43.17, start: 0.036281, bitrate: 862 kb/s
Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 720x406 [SAR 406:405 DAR
16:9], 732 kb/s, 23.98 fps, 23.98 tbr, 24k tbn, 47.95 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 128 kb/s
(default)
Metadata:
handler_name : SoundHandler
Input #1, srt, from '/Users/JW/Dropbox/T10/SBRI/_code/subs/3rd person present tense (303)/srt_file.srt':
Duration: N/A, bitrate: N/A
Stream #1:0: Subtitle: subrip
[srt @ 0x7fd082005c00] sub2video: using 720x576 canvas
[libx264 @ 0x7fd082801200] using SAR=406/405
[libx264 @ 0x7fd082801200] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
[libx264 @ 0x7fd082801200] profile High, level 3.0
[libx264 @ 0x7fd082801200] 264 - core 142 r2495 6a301b6 - H.264/MPEG-4 AVC codec - Copyleft
2003-2014 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0
analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1
trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=6
lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=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=23 scenecut=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 '/Users/JW/Dropbox/T10/SBRI/_code/videos_final/3rd person present tense
(303)_subs.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf56.15.102
Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 720x406 [SAR 406:405
DAR 16:9], q=-1--1, 23.98 fps, 24k tbn, 23.98 tbc (default)
Metadata:
encoder : Lavc56.13.100 libx264
Stream #0:1(und): Audio: aac (libvo_aacenc) ([64][0][0][0] / 0x0040), 44100 Hz, stereo,
s16, 128 kb/s (default)
Metadata:
handler_name : SoundHandler
encoder : Lavc56.13.100 libvo_aacenc
Stream mapping:
Stream #0:0 (h264) -> overlay:main (graph 0)
Stream #1:0 (srt) -> overlay:overlay (graph 0)
overlay (graph 0) -> Stream #0:0 (libx264)
Stream #0:1 -> #0:1 (aac (native) -> aac (libvo_aacenc))
Press [q] to stop, [?] for help
sub2video: non-bitmap subtitle
frame= 1029 fps= 71 q=-1.0 Lsize= 4319kB time=00:00:43.17 bitrate= 819.6kbits/s
video:3612kB audio:675kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead:
0.751962%
[libx264 @ 0x7fd082801200] frame I:44 Avg QP:17.59 size: 16172
[libx264 @ 0x7fd082801200] frame P:495 Avg QP:22.62 size: 5016
[libx264 @ 0x7fd082801200] frame B:490 Avg QP:23.28 size: 1027
[libx264 @ 0x7fd082801200] consecutive B-frames: 24.2% 34.4% 7.6% 33.8%
[libx264 @ 0x7fd082801200] mb I I16..4: 27.2% 43.8% 28.9%
[libx264 @ 0x7fd082801200] mb P I16..4: 5.9% 14.8% 2.9% P16..4: 31.1% 10.7% 4.3% 0.0%
0.0% skip:30.3%
[libx264 @ 0x7fd082801200] mb B I16..4: 0.2% 0.5% 0.2% B16..8: 26.2% 3.3% 0.6%
direct: 1.1% skip:67.8% L0:40.7% L1:52.4% BI: 6.9%
[libx264 @ 0x7fd082801200] 8x8 transform intra:57.6% inter:72.8%
[libx264 @ 0x7fd082801200] coded y,uvDC,uvAC intra: 41.3% 60.2% 22.0% inter: 9.1% 14.5% 0.6%
[libx264 @ 0x7fd082801200] i16 v,h,dc,p: 41% 25% 11% 22%
[libx264 @ 0x7fd082801200] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 29% 20% 23% 4% 5% 6% 5% 5% 4%
[libx264 @ 0x7fd082801200] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 29% 20% 12% 5% 8% 9% 7% 6% 4%
[libx264 @ 0x7fd082801200] i8c dc,h,v,p: 53% 20% 21% 6%
[libx264 @ 0x7fd082801200] Weighted P-Frames: Y:14.1% UV:9.9%
[libx264 @ 0x7fd082801200] ref P L0: 68.6% 14.5% 12.3% 4.2% 0.4%
[libx264 @ 0x7fd082801200] ref B L0: 91.7% 7.5% 0.8%
[libx264 @ 0x7fd082801200] ref B L1: 98.4% 1.6%
[libx264 @ 0x7fd082801200] kb/s:689.28
Che cosa sto facendo di sbagliato?