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7 votes
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Is there any ffmpeg command for knowing max bit rate of a video?

That max_bit_rate is a a tag written by some encoders, when set by the user in the export dialog box. It is not an indication of the maximum bitrate found if you were to survey the encoded bitstream. ...
Gyan's user avatar
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6 votes
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It is better to have more B-frames or more P-frame for video streaming?

"Q: Is it better to have more B-frames or more P-frame for video streaming?". From: https://en.wikipedia.org/wiki/Video_compression_picture_types The three major picture types used in the ...
Rob's user avatar
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5 votes

Please explain video bit rate further

Per the OP's request, I will attempt to explicitly answer his single-sentence questions. First I need you to define bit rate. Bit rate is the number of bits per second used to encode a video stream (...
Michael Tiemann's user avatar
4 votes

Why is ffprobe showing another bitrate than the one I encoded with?

Why is the duration changed? MP3s may not display accurate duration, depending on whether a Xing header was written, and whether the MP3 encoding is Variable Bit Rate (VBR) or a Constant Bit Rate (CBR)...
Gyan's user avatar
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3 votes
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Does increasing the framerate while not changing the content affects compression quality?

This depends on the specific encoder, and the compression standard, by itself, may not have anything to say about it. x264, which encodes to H.264, takes frame duration, into account, in its ...
Gyan's user avatar
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3 votes
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Is there a mathematical equation to compute the bitrate of a Cisco H.264 stream?

No, because it's content dependent. Video with high motion contains more information than a nearly still scene does. Hence it takes more bits to encode.
SlimSCSI's user avatar
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2 votes
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Bit rate reduction when converting 60fps footage into 30fps?

In theory, if the number of keyframes and their placement were about the same, as decided by the encoder, then yes, you can reduce the bitrate to half and retain the same quality. In practice, the ...
Gyan's user avatar
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2 votes
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how to measure bitrate of video over time

It does not make sense to speak of the size of an encoded frame in an inter-coded video stream, which is typical of MPEG-X videos. I-frames are self-contained but P- and B- frames are predicted frames ...
Gyan's user avatar
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2 votes

Is there a way to improve quality for videos with snow/confetti/LCD in background?

Yes this feature exists, but it is not widely used yet. Texas Instrument developped such solution, called SmartCodec, which looks to be implemented in a Samsung video surveillance system: Megapixel ...
RawBean's user avatar
  • 163
2 votes

How to concatenate 2 MP4 videos to output of certain bitrate?

Step 4 (first attempt) will work if you re-encode the 2nd video like the first (without the filters). What's happening is that besides the timescale difference between CC's output and ffmpeg's (which ...
Gyan's user avatar
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2 votes

"The sample rate of the two audio tracks is different"

To force to 44100 Hz, command template is ffmpeg -i old.mp4 -map 0 -c:v copy -c:a aac -ar 44100 new.mp4
Gyan's user avatar
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2 votes

Is there any ffmpeg command for knowing max bit rate of a video?

See https://github.com/zeroepoch/plotbitrate It uses ffprobe under the hood and can output an xml file. Here's an example output.svg: (Although it is slow - almost as slow as transcoding, because it ...
Jeff Ward's user avatar
  • 121
2 votes

Why I can't check the bit rate on some videos?

For mkv files, you can use mkvpropedit —add-track-statistics-tags to add stream level data.
Jeff Rice's user avatar
2 votes

ffmpeg + libfdk_aac + vbr => wrong "BitRate_Mode"

The issue was caused by ffmpeg/libavformat/movenc.c::mov_write_esds_tag, it can't find max_bitrate. To solve it you should specify audio bitrate -b:a 128k along with -vbr 4. Then mp4's ESDescriptor ...
Andrew Trofimov's user avatar
2 votes

Does it help to record at a higher bitrate and render at a lower one?

Yes there is. When you edit a video, you're making cuts to the existing stream that has been encoded. Lossy video codecs (like h264, which most people use when they make an mp4 for online viewing) ...
tomh's user avatar
  • 7,650
1 vote

Recompressing 1080p h264 collection to HEVC - Target Bitrate For Minimal Loss

I've transcoded some of my AVC (h.264) 1080p movies to HEVC (h.265) with 2 pass encoding (using my GPU) and target bitrate set to 50% of original. The other streams (like audio and subtitles) were ...
mareccs's user avatar
  • 11
1 vote

Why is the EOS M6 Video Bitrate lower than the EOS 1200D/T5?

That would be a great question for Canon, because only the manufacturer can provide the reasons considered when producing a new model. I only can venture a guess that the M6 is a smaller camera that ...
Rusty Core's user avatar
1 vote

Why I can't check the bit rate on some videos?

Bitrate isn't calculated from stream size, but the number is saved in file as special field/metadata. Now, the problem with ffmpeg (or rather libmatroska) and Matroska (MKV) muxer is it doesn't save ...
Krzysiu's user avatar
  • 111
1 vote
Accepted

Video with lower bitrate resulting from joining two video files

Your program probably re-encoded the resulting video file from scratch and used whatever setting it considered okay. If you want to have more control about the process and/or do not want it to re-...
Michael Auerswald's user avatar
1 vote
Accepted

Using youtube-dl: Does adaptive bitrate (ABR) affect image quality?

Adaptive streaming is accomplished by switching between pre-encoded streams of different bitrates and/or resolutions. But the bitrate within any given pre-encoded stream does not vary too much. YT-DL,...
Gyan's user avatar
  • 33k
1 vote

How to fix invalid bitrate with ffmpeg

Here is what i would be doing to try to resolve this: Check the video with fprobe -show_streams note how many frames there are. From that and the knowledge of the total duration it can be possible to ...
v010dya's user avatar
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1 vote
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Does bitrate also mean the internet speed I need to have?

Yes. But you should have a little overhead as well, so you probably need about 150Mbps for this. Something like huffyuv could give about a 50% reduction, or a lossy codec would give 95% or more ...
SlimSCSI's user avatar
  • 1,070
1 vote

If the environment being captured on a video stream becomes less complicated, does the bit rate and latency decrease?

Like much with technology (and life), it depends. You didn't specify what software, protocol, or codec you are streaming with, so there are quite a few variables. Will the bit rate drop? If you are ...
Michael Liebman's user avatar
1 vote

If the environment being captured on a video stream becomes less complicated, does the bit rate and latency decrease?

so all that is captured in the live video stream is a red light bulb and a black background No. You can't get black background. You will get any possible type of noises, many shadows and all kinds ...
bukkojot's user avatar
  • 675
1 vote

ffmpeg live streaming to Periscope: bitrate appears too high

I missed the -re flag that would limit speed of reading the generators at a speed of playback. My ffmpeg was streaming data to Periscope as fast as it can, much faster than a live stream would, thus ...
Serge's user avatar
  • 189
1 vote

ffmpeg live streaming to Periscope: bitrate appears too high

You can use option -ab, like -ab 32000 for 32kbit/s bitrate audio. But here may be problem: not all codecs (encoders) can support so small bitrate. For example, libaacplus can do even smaller, but it ...
bukkojot's user avatar
  • 675
1 vote

Is there any ffmpeg command for knowing max bit rate of a video?

I wrote a simple tool to do this, called ffmpeg-bitrate-stats. It requires Python and ffmpeg installed. Install it via pip: pip3 install --user ffmpeg-bitrate-stats Then run it on a file: ...
slhck's user avatar
  • 1,015
1 vote

Is there a way to improve quality for videos with snow/confetti/LCD in background?

Is there any technique (encoding/compression/etc.) that can improve the quality of the foreground elements when such a background is present in the shot? I don't know of any encoding algorithm that ...
MoritzLost's user avatar
  • 5,412

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