I'm using sox to convert some mp3 files to wav for a project. The problem is that the software that plays the files does not have the media name for the element it is playing. I can't seem to find a win32 cli tool to read the header of the wav file and write what I need to it.
Sox will read the header but it's not showing the title of the media element that was inserted with the old software I used. I just couldnt automate it or I would have used it instead.
I have determined the info is written in either CART CHUNK section or just to the file headers. I can't figure out to write my own data there.
The way I was able to do this was with this project: https://github.com/JamesHeinrich/getID3
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I am using javascript to capture audio data from MediaRecorder, and base64 encode it so I can send it back to the web server where it can be saved for later playback.
data:audio/webm;codecs=opus;base64,GkXfo59ChoEBQveBA...(too much data to post, but you get the idea)
I can put that data into an HTML5 audio element's .src field, and play it back on a Chrome browser just fine. But Safari can't handle the data in that format, I guess it doesn't support the opus codec.
One solution for me would be to figure out how to write the audio data into a properly formatted .webm container file, and then use ffmpeg.exe to convert it to some other Safari friendly format.
But I don't know the file format for .webm file - I'm looking for tips or guidance how to write such a .webm file.
Anybody have any suggestions, libraries, or tips to write data like above to a .webm file? I prefer a C# .net answer, but javascript will also do, or any examples are appreciated.
Well, I got a tip from smart developer (earnabler) that if I stripped off the header portion of the content:
"data:audio/webm;codecs=opus;base64,"
and decoded just the base64 portion:
"GkXfo59ChoEBQveBA...(too much data to post, but you get the idea)"
...back to binary (example in C#):
byte[] decodedBinaryData;
decodedBinaryData = Convert.FromBase64String(encodedBase64String);
...and wrote that binary to a file with a matching file extension (.webm in this example), that the file would be a properly formatted file of that type understandable by other media software.
Lo and behold, it was! I could play the file in MediaPlayer, or QuickTime, or whatever, and could use FFMPEG to convert it to other types.
So that gives me a pathway to save/use/convert the media in many ways. Problem solved.
I'm building a project where people can upload files, I would like to then display those files in a browser where people can interact with them (vote, comment etc)
However, this means I need to programatically build the html depending on the format of the video or image. Is there a way to feed a file (or filename) into a library, and determine whether I need to display it in a video element or an image element? Even a list of video formats vs image formats would help but I haven't seen anything in regards to that.
No module can reliably determine the file type. The user could either change the extension or even the magic number of the file to obfuscate it. The only reliable way it to try to pass file to some image / video transcoder to let it decide or error out if the format is invalid. This way you know you are working with known formats since all files are transcoded to your specific extensions. That could be mp4 or png. I recommend using handbrake for videos and sharp for images. Leaving the NPM links down below:
https://www.npmjs.com/package/handbrake-js
https://www.npmjs.com/package/sharp
I'm writing in raw PHP on Linux using the tcpdf library.
The core question is that while creating a PDF with tcpdf I'd also like to kick off an audio file for the user...but tcpdf considers that TCPDF ERROR: Some data has already been output, can't send PDF file so I'm looking for a way to play an audio file at PDF generation without tcpdf considering that 'interfering output'.
I can successfully generate my wanted PDF within my browser using the tcpdf library and calls. But I would also like to play an audio when this happens - that might say "This is your generated PDF. You can print it now...etc"
So I'm wanting to put the HTML audio syntax within my php script.
However if I try to include an audio clause before the tcpdf->output, tcpdf will play the audio but say that output has happened before the tcpdf output and will not generate the PDF image. Flow stops after the tcpdf->output command - it successfully generates the PDF but it does not return for additional lines so I can't place the audio line after the output call.
So I guess I'm looking for a "hidden" audio although I've tried hidden attributes within the HTML audio syntax but still tcpdf flags it as "output has happened". Thank you.
Well, obviously, you can do that simply by
generate the PDF into file (not to the client directly -- 'F' switch).
output your audio file to the client and let it platy
output a link/Javascript redirection to the generated PDF file.
Because you didn't provide any code in your question I do not provide any either, but I believe it is already understandable.
I'm trying to rebuild a video file from a Smooth Streaming server. Smooth Streaming serves fMP4 files which are regular MP4 files without neither their FTYP nor their MOOV atoms.
All the informations stored in those atom are placed into a Manifest XML file, which I have.
Is there a way to programmatically rebuild the original MP4 file, either by:
rebuilding a new file straight from H264/AAC content located in MDAT
(and picture format infos); or
rebuilding FTYP and MOOV atoms
Or else, is there a tool which can merge fMP4?
Yes. It is completely possible.
You can do this with FFmpeg. Study the mov.c [MP4 demuxer] from libavformat.
You will need to complete the MP4 in memory with all data that is "missing" in the fMP4. In other words, when you need an atom that doesn't exist in fMP4 [almost all], you will have to input all information hard-coded (such information, most of them come from the manifest).
It's not easy... but for sure it's possible. I've done by myself. Unfortunately the code is not my property.
Good luck! ;-)
UPDATE: the PIFF format specification will be very useful (http://go.microsoft.com/?linkid=9682897) so one can understand what is already in the fMP4 and what is not!
It is simple to rebuild a mp4 file, if there are ism and ismc file which are related to fragmented mp4 files.
It is requested that you should know media type, codec type, codec specific data and time scale of each trak to rebuild a moov and ftyp atom.
these information can be retrieved from ism and ismc file.
you can retrieve a media type of each track from the ism file.
you can retrieve codec type, codec specific data and time scale of each track from the ismc file.
simply speaking, ism/ismc files are meta data for server and client so that you can rebuild meta data(ftyp, moov atom) for a mp4 file.
I would like to convert .rm (RealPlayer Media) file to MP3 or another format?
First, I successfully managed that using VLC but the quality was not good. Then I tried the Real Alternative codec with DirectShow, this also worked ok, but then I found that the codec is no longer developed because RealNetworks sued the developer.
Now, I have installed the RealPlayer and I am trying to use it's DirectShow filters to convert .rm to .mp3 but without success:( (Actually after adding RealPlayer Transcode filter and choosing a file the GraphStudio crashes.)
Is there a legal way to programmatically convert .rm file to another format? How to make RealPlayer to programmatically convert files? Do you have any hints or examples, how to use RealPlayer Transcode filter? (I am new to DirectShow.)
UPDATE to make the question more concrete: How can I list implemented interfaces and its members of RealPlayer Transcode filter? I have not found any documentation:( (The GraphStudio says it has 0 pins and just common properties.)
You need to build a DirectShow graph to read and decode .rm, then compress audio into MP3 and write it into a file. This is similar to recompressing an AVI file, described in some detail on MSDN: Recompressing an AVI File. You just have audio without video there, and the container formats are different.
UPDATE: There is no way to reliably list implemented interfaces in COM. Sometimes you can find this out by checking the type library, however a lot of DirectShow filters are coming without it. Typically, you need an SDK header file from the filter vendor to get a definition of implemented so called 'private' interfaces.