Re: [FFmpeg-user] ffmpeg CL translation from Linux to Windows
On 11/13/2015 8:37 PM, MrNice wrote: On 13/11/15 15:35, Claudiu Rad wrote: On 11/8/2015 8:25 PM, MrNice wrote: Hi, I need to compare ffmpeg behaviour between Linux and Windows. I installed Virtualbox on my Fedora host and Win 8.1 as guest. Now I need to translate the Linux CL ./ffmpeg -debug 1 -xerror -f pulse -ar 44100 -ac 2 -channel_layout stereo -thread_queue_size 512 -i alsa_input.pci-_00_14.2.analog-stereo -f v4l2 -ts mono2abs -channel 1 -video_size 720x576 -pix_fmt yuyv422 -thread_queue_size 512 -i /dev/video0 -c:v libx264 -vf setfield=tff -preset slow -qp 0 -x264opts tff=1 -aspect 4:3 -pix_fmt yuv422p -c:a pcm_s16le -channel_layout stereo /Store3/Test/t_`date +%Y%m%d_%H%M`.mkv -aspect 4:3 -f sdl "Dazzle output". so you are trying to compare the capture from a USB device but want to run windows inside a VM? i surely wouldn't recommend that, there are many many things that may go wrong. it's way better to install windows side-by-side with linux on a different drive/partition, make all updates, install all drivers and let him do his job without linux/VM layers. and please.. when investigating and posting things, resume to simplest command line possible that reproduces the issue. [...] Back to the point; Windows is only to check if the bug occurs as well. I don't want as much as possible to use Win. Last time I used it was NT/2000... and I don't have an available computer for it and don't want to damage my running config. Anyway, first is to know if it's working, so I need to test. i don't know much about this and sorry for not following your entire topic and issue due to time constraints, but i still have some remarks that may help: - your errors contain negative timestamps which is weird. did you try all timestamp related ffmpeg options like vsync, copyts, start_at_zero, etc. to check their effects? - frankly if issue reproduces with basic command line, considering the fact you are an isolated case, i would judge that the issue is related to your equipment/software? that's why one of my suggestions were to try a completely different capture card. another option is indeed, try windows via directshow. as much as you don't like it, actually from my experience in some video/streaming areas its the best option available. make sure however you use latest windows OS and try first default drivers for your capture device and eventually then explicitly install latest one if applicable. i wouldn't be surprised if your issue is hardware+driver+OS. in my experience i've seen situations where for example: mac + os x + blackmagic card + latest os x drivers + streaming tool osx version => periodic crashes . mac + windows + blackmagic card + latest windows drivers + streaming tool windows versions => complete success - if you try windows, please don't do it inside a VM. the data path from and to your capture device has much more failure points. to rule out windows, i strongly recommend you to try as i've said, clean, latest one (windows 10 now), completely updated -- jazzman ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user
Re: [FFmpeg-user] MPEG-2 CBR
On 1/15/2015 1:30 PM, Janez Miklavcic wrote: f:/ffmpeg/bin/ffmpeg.exe -f dshow -video_size 720x576 -framerate 25 -pixel_format bgr24 -i video=VidBlaster VVD -mpegts_service_id 0x002 -metadata service_name=POLANC TV INFO -metadata service_provider=SVISLAR telekom d.o.o. -vcodec mpeg2video -b:v 2000k -minrate:v 2000k -maxrate:v 2000k -bufsize 20k -q 3 -s: 720x576 -r 25 -g 50 -f mpegts -mpegts_pmt_start_pid 0x3E8 -mpegts_start_pid 0x3E9 -muxrate 20M udp:// 232.8.8.8:55002?pkt_size=188 what's this? what would you expect it to do if you tell it to go at 20Mbit? -muxrate 20M Although bitrate is set to 2Mbit/s it jumps to 20 Mbit/s. Thnaks, Janez 2015-01-15 12:03 GMT+01:00 Roger Pack rogerdpa...@gmail.com: On 1/14/15, Janez Miklavcic svisla...@gmail.com wrote: Dear All, I've been trying to achive constant video bitrate for mpeg-2 with different settings of ffmpeg (windows) but no success. The source was dshow. I've been testing video bitrate with TS reader. Can you tell me if video CBR in MPEG-2 is possible or not and if yes can you send me the settings. uncut command line and console output of failing example please? ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user -- jazzman ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user
Re: [FFmpeg-user] Stretch
On 1/14/2015 9:25 AM, Vladimir Bilichenko wrote: Hi. I have a question about video stretching. I have a video( https://www.dropbox.com/sh/5mw6hvgw170ov8b/AADABGroGqbSg_a9INZiesrQa?dl=0) width = 840, height = 922. I need to change the size of the video to 1920x1080 it must be stretched. Output file should be .mp4. Can some one help me with that? Thats not working for such input resolution width = 840, height = 922. yes, it works, but you probably also want to set SAR 1:1: ffmpeg -i input_file -vf 'scale=1920:1080,setsar=1' other_encoding_parameters output_name.mp4 ffmpeg -i input_file -s 1920x1080 other_encoding_parameters output_name.mp4 ? -- jazzman ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user
Re: [FFmpeg-user] Audio channel mapping of stereo channel without re-encode
On 8/21/2014 5:30 PM, Carl Eugen Hoyos wrote: Hanno Klamke Hanno.Klamke at streamlab.net writes: I would like to transcode a video into several outputs. From the source audio I would like to take either only the left or the right channel into my outputs. While only transcoding the video and copy the audio. I also confronted something similar a while ago. This cannot work. (And even if you know nothing about audio encoding, you should be able to imagine why it cannot work for codecs that actually do compress in a useful way.) Indeed, you are right. But from what I know so far, this is because the level of data access that we have now is either at the stream level (audio, video, subtitles, etc) after demuxing, either somehow at the uncompressed frame level after decoding. However, this doesn't change the fact that it would be really nice if we could have an intermediate access level in audio streams case (and I think this is the only one case where one stream actually packs multiple 'substreams' at least in abstraction) and we could really remap channels as we like without reencoding. But I assume that this would be a nightmare because it must be implemented at audio codec level, thus, for every codec alone.. However, it would be something nice for the future, would certainly optimize things. Carl Eugen ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user -- jazzman attachment: jazzman.vcf___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user
Re: [FFmpeg-user] -threads option has no effect
On 8/12/2014 1:56 PM, Rohit Talwar wrote: Hi Thanks for looking into my query. I have a main java program within which I run ffmpeg (using exec). Often there comes a scenario wherein my program needs to create 4+ different instances of ffmpeg program for converting files into different formats. When this happens the cpu gets 'too busy' running the ffmpeg instances which affects the performance of my java program. I think lowering the priority(using nice or start /LOW ) of the ffmpeg process might be a possible strategy to solve this, but would be glad if you can help me point towards a platform independent solution. On Tue, Aug 12, 2014 at 3:39 PM, James Darnley james.darn...@gmail.com wrote: On 2014-08-12 11:59, Rohit Talwar wrote: Hi I ran the command - ffmpeg -threads number of threads -i my file.avi Perhaps you should not be using it as an input option. or to expand this a bit for regular people that don't understand that order matters: try to put threads option AFTER the input file, because most options apply to the next input/output file in the command line, like this: ffmpeg -i my file.avi -threads number of threads ... output don't know if it would do the job for you but it should. also, lowering process priority and letting ffmpeg use all available resources would be my recommendation for maximum performance in all cases. target.mp4 hoping it would not hog my cpu and consume only one core of my machine. But it was still taking up all of my cpu. I ran the following experiments to confirm my suspicion that including the -threads option has no effect on cpu usage. Why do you not want it to use as much CPU as it can? If this is a desktop that you are using at the same time you should lower the priority of the ffmpeg process. ___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user -- jazzman attachment: jazzman.vcf___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user
[FFmpeg-user] copy input i-frames structure to output
hello, i need to do transcoding of an mp4 video and i want to keep the i-frame structure the same as in the original video. i've searched info on this but couldn't find out if it is even possible with ffmpeg although my wild guess is that it should be. furthermore, to complicate things, ffmpeg should be just a simple box in a processing chain and pre-scanning the input is not acceptable. basically, i would like to somehow tell ffmpeg during encoding that for each video frame that it encodes, first check if it was a keyframe in the original video. if yes, make it also in the output, if no, don't do it. any ideas? thanks! -- jazzman attachment: jazzman.vcf___ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user
