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#1
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Incredible, free, video editing software
I found some software today that is so amazing I
just wanted to share it, in case anyone might benefit: Avidemux - Open source video editor. I wanted a way to rotate a video. What I found was a program that does to video what Photoshop does to images. I resized, cropped, rotated and changed the format of a MOV file, all in one operation. It took about 1 minute to process a 134 MB MOV and get a smaller, rotated, cropped, 23 MB MP4. The software can edit colors, audio elements, cut, copy and paste, add subtitles, borders... And the installer is only about 12 MB, with no special dependencies. What I'm using on XP: https://sourceforge.net/projects/avi...atest/download A slightly later version that says it's not XP-compatible. This page also has a 64-bit version: http://fixounet.free.fr/avidemux/download.html Basic instructions: http://www.howtogeek.com/108584/how-...with-avidemux/ |
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#2
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Incredible, free, video editing software
Mayayana wrote:
I found some software today that is so amazing I just wanted to share it, in case anyone might benefit: Avidemux - Open source video editor. I wanted a way to rotate a video. What I found was a program that does to video what Photoshop does to images. I resized, cropped, rotated and changed the format of a MOV file, all in one operation. It took about 1 minute to process a 134 MB MOV and get a smaller, rotated, cropped, 23 MB MP4. The software can edit colors, audio elements, cut, copy and paste, add subtitles, borders... And the installer is only about 12 MB, with no special dependencies. What I'm using on XP: https://sourceforge.net/projects/avi...atest/download A slightly later version that says it's not XP-compatible. This page also has a 64-bit version: http://fixounet.free.fr/avidemux/download.html Basic instructions: http://www.howtogeek.com/108584/how-...with-avidemux/ D/L it. Have not tried editing but tried it for changing formats. Changed an AVI to MP4 and got a larger file size. Then changed another MP4 to AVI and also got a larger file. -- GW Ross Time flies like an arrow; fruit flies like a banana. |
#3
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Incredible, free, video editing software
| D/L it. Have not tried editing but tried it for changing formats.
| Changed an AVI to MP4 and got a larger file size. Then changed | another MP4 to AVI and also got a larger file. | I just tried that. Changing a 48 MB mp4 to AVI came out at 77 MB. Changing that back to an mp4 came out at 74 MB. I tried a little testing. Switching the video output quantization setting from H.263 to MPEG and switching macroblock decision from QPel8 to none produced an identical video of 179 MB rather than 74. What did I change? I really don't know. Then I went into the video settings and selected a target size of 40 MB and got a video of 47 MB, about 2/3 the size of the original. I can't assess the quality. They all look the same to me. But they were not high quality video starting out. They're just MP4s. This page seems to shed a little light: https://en.wikipedia.org/wiki/Video_..._picture_types There seems to be some very complex compression technology, similar to the combination of quality and compression alogrythms that can be applied to images. I'm not an expert on either audio or video, so I don't understand most of the options. I don't know the differences any more than most people know a BMP from a JPG. I'd be curious to hear what a professional would say. In my case I have a friend who had a 134 MB video of birds, apparently taken with a iphone. It was sideways and giant. I found it almost effortless to rotate it, crop it, resize it and change it from MOV format to mp4 in Avidemux. That allowed me to make two other versions: One desktop size at 23 MB and one for emailing at 4.5 MB. I now know I probably could have shrunk those by half, only requiring a longer processing time. Prior to that I had been searching for hours just to find a way to rotate the video. Windows Movie Maker for XP wouldn't open MOV. Once I got the MOV converted to AVI, Movie Maker closed with no error when I tried to rotate the video. The Vista version just showed a shaking image and also failed to rotate. Another program was a 20 MB download and needed .Net. (The Win7 version of Movie Maker requires signing up for Microsoft's online nonsense.) Handbrake could convert but didn't do much else and had limited format options. VLC has impressive options but the GUI is quirky and I had a hard time getting a rotated video without messed up audio. Avidemux was, by far, the most functional option I found, and seems to be comparable to software costing hundreds of dollars. Thanks to your comment I may do some research, now knowing that a few settings changes can greatly affect all sorts of things. Maybe someone reading this can shed more light on the technology. |
#4
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Incredible, free, video editing software
Mayayana wrote:
| D/L it. Have not tried editing but tried it for changing formats. | Changed an AVI to MP4 and got a larger file size. Then changed | another MP4 to AVI and also got a larger file. | I just tried that. Changing a 48 MB mp4 to AVI came out at 77 MB. Changing that back to an mp4 came out at 74 MB. I tried a little testing. Switching the video output quantization setting from H.263 to MPEG and switching macroblock decision from QPel8 to none produced an identical video of 179 MB rather than 74. What did I change? I really don't know. Then I went into the video settings and selected a target size of 40 MB and got a video of 47 MB, about 2/3 the size of the original. I can't assess the quality. They all look the same to me. But they were not high quality video starting out. They're just MP4s. This page seems to shed a little light: https://en.wikipedia.org/wiki/Video_..._picture_types There seems to be some very complex compression technology, similar to the combination of quality and compression alogrythms that can be applied to images. I'm not an expert on either audio or video, so I don't understand most of the options. I don't know the differences any more than most people know a BMP from a JPG. I'd be curious to hear what a professional would say. In my case I have a friend who had a 134 MB video of birds, apparently taken with a iphone. It was sideways and giant. I found it almost effortless to rotate it, crop it, resize it and change it from MOV format to mp4 in Avidemux. That allowed me to make two other versions: One desktop size at 23 MB and one for emailing at 4.5 MB. I now know I probably could have shrunk those by half, only requiring a longer processing time. Prior to that I had been searching for hours just to find a way to rotate the video. Windows Movie Maker for XP wouldn't open MOV. Once I got the MOV converted to AVI, Movie Maker closed with no error when I tried to rotate the video. The Vista version just showed a shaking image and also failed to rotate. Another program was a 20 MB download and needed .Net. (The Win7 version of Movie Maker requires signing up for Microsoft's online nonsense.) Handbrake could convert but didn't do much else and had limited format options. VLC has impressive options but the GUI is quirky and I had a hard time getting a rotated video without messed up audio. Avidemux was, by far, the most functional option I found, and seems to be comparable to software costing hundreds of dollars. Thanks to your comment I may do some research, now knowing that a few settings changes can greatly affect all sorts of things. Maybe someone reading this can shed more light on the technology. I can comment as a noobie :-) I've burned a total of three dual layer DVDs, so that's some idea of my "depth of experience" :-) You can divide the techniques up. 1) Uncompressed. RGBA. Huge datarate. The format that comes off a hardware capture device maybe. I might get a 200GB video from this, from my ****ty WinTV card. 2) Lossless compression. Huffyuv or FFV1. Generally achieves up to 3:1 compression. Same as (1), but saves you some disk space. Tends to chew up CPU when editing (i.e. you may regret your choice at that point). Now, your (archived) original capture goes from 200GB to 70GB. 3) Lossy compression. Compression ratios of around 100:1 or so. DCT - discrete cosine transform. Frequency domain analysis. Discarding high frequency content and sharp edges. Tossing detail humans don't notice, when there is a lot of action. - In addition to compression of a frame, there is a possibility to do temporal compression, look at the frames nearby, and come up with a difference used for prediction of the next frame. Frame types then are IBP, one of the frame types having a lot of bits, the others representing differences. A repeating pattern of them is a GOP or group of pictures. A GOP of 12 or 15 might be typical, around 1/2 a second of video before the next I frame. Snipping video can be seamless, if done on GOP boundaries. An "open" GOP, one GOP can depend on an adjacent GOP. With a bit of a bandwidth penalty, it's possible to encode with a "closed" GOP, so each group of pictures is independent of the next group. Which makes fast forward and fast reverse work better. - It's possible to use MJPEG compression, and make all the frames independent of one another. The compression is better than (2), but less than a full blown DCT method with temporal thrown in. One advantage of MJPEG as a compressor, is every core on your CPU can work on MJPEG compression of a frame at the same time. A disadvantage, is JPEG tends to have mathematical "ringing" and screwed up color fringes. Attempts to do screen capture video with this, didn't look good. Vector Quantization - Cinepak 5X bigger than modern lossy compression methods. Compression is *very* slow (less than one frame a second). Compressor is single threaded (split video in sections, put each section on a separate CPU core for compression). Video has excellent seek characteristics (fast forward is like butter). Decompression is possible on absolutely gutless processors. Nobody used it but me :-) https://en.wikipedia.org/wiki/Cinepak I found a nice animation of how the compressor works, but don't seem to have bookmarked it. ******* When you use a DCT method, you can do things like define a "quality" or Qfactor. At Q:2, that says you want absolutely best quality, and the bitrate simply leaps up to make that happen. If there is an explosion in the video, maybe it takes 50Mbit/sec to full represent it, without blocky artifacts. The other constraint you can apply, is bandwidth. You define min bw avg bw max bw buffer size The average might be 3900Kbit/sec, the min 0, the max 8000Kbit/sec. The buffer a bit less than 2MB (the size of some cheap DVD player read-ahead buffer). If there is an explosion, the Qf leaps up to 32, the quality is ****, but the segment of video stays below 8000Kbit/sec. When the video scene content is still, the Qf drops to 2 (excellent quality), the bitrate becomes minimal, the read-ahead buffer can refill itself. So there is a model based on player characteristics, with enough slop to handle a variety of video content. The compressor profile can work on either basis (Qf constrained or bitrate constrained), based on the preference of the person doing the video edit. If you use FFMPEG, you get to set these things. You can dial the knobs until you're happy with the space versus quality tradeoff. In this example, the ntsc-dvd specification, causes the usage of mpeg2video codec for video. Not sure what the default audio codec is. ffmpeg -i G:\some.avi -target ntsc-dvd -aspect 4:3 -g 15 -bf 2 -sc_threshold 1000000000 -b:v 3900k -maxrate 8000000 -minrate 0 -bufsize 1835008 -pass 1 -y NUL ffmpeg -i G:\some.avi -target ntsc-dvd -aspect 4:3 -g 15 -bf 2 -sc_threshold 1000000000 -b:v 3900k -maxrate 8000000 -minrate 0 -bufsize 1835008 -pass 2 F:\output.vob ffmpeg -i F:\output.vob -vcodec copy F:\video.m2v ffmpeg -i F:\output.vob -acodec mp2 -ac 2 -b:a 192k F:\video.mp2 That's two pass conversion, with the first two commands. The first pass, generates a logfile in the working directory. The second pass recognizes the logfile by name, and applies the information during the actual final (second pass) compression. By having Q or bandwidth info to work with, it knows a "bad section" is coming or whatever. The logfile is relatively tiny, so doesn't contain a representation of the video at all. The last two commands split the video into two separate files. One video, one audio. Which is sometimes required by other authoring tools. If you want to put a French and an English soundtrack on your output media, having separate streams comes in handy before final re-assembly. The authoring tool may allow you to build a menu, to select the language before you press play. Video can also be coded CBR or Constant BitRate, but I've not discovered a reason to do that yet. The above assumes VBR or variable bit rate. ******* And these methods are designed for subsets of all video content. The DCT compressors might be good for motion pictures, but a poor choice for cartoons. Since I don't collect cartoon video, I have no idea what is used there. HTH, Paul |
#5
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Incredible, free, video editing software
| I can comment as a noobie :-) I've burned a total
| of three dual layer DVDs, so that's some idea of | my "depth of experience" :-) | It's a lot more than I knew. Thanks. I realize now, in thinking about it, that videos such as Youtube videos are usually fairly poor quality. Slight blurs are common when there's movement. |
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