When we play a mp3 file, an image is shown in audio player (generally is album poster or something related). How is that image stored within mp3 file ?
The image is stored in form of an ID3 tag in the MP3. ID3 tag is basically metadata which contains information like which artist made the song, which album it is from, etc.
The cover images are fetched from online collections (e.g. from Last.fm) and saved in the file.
Related
I have a PDF file that consists of the following image:
I used this image in a latex document in overleaf. The original file is 14MB large so it took overleaf some time to load it. Surprisingly, the loading sequence is such a beautiful video that I would like to make a movie out of the layers of this pdf image. I recorded my screen to get a preliminary version of this movie, but you can see that the video is not perfect and especially at the end the video it is quite far from being smooth.
You can find both files (original PDF file of the coils & the video recorded from screen) here: Documents
Is there an easy way to transform the layers of this PDF image into a movie?
I guess the first question is how can I extract the different layers of this PDF image?
Thank you very much in advance,
Jimmy
I'm trying to organize my photo collection and convert .mov files to .jpeg files while retaining all of the meta data that has been stored. I'm running into a problem with Apple's "Live Photos" though...
I recently downloaded all of the photos from my iCloud account and found that many have been stored as .mov files as "Live Photos". As I only want to include photos in this collection, I'd like to convert all of these .mov files to .jpg files.
So... I'm trying to use python and shell commands to do this. Here's an extract of my code:
# Convert the .mov file into a series of jpegs using ffmpeg
os.system(f'ffmpeg -i {movie} -r {numFrames} -map_metadata 0 -movflags use_metadata_tags {imageRoot}_%0004d.jpg')
# ... some code to find the best slice of the movie to keep as an image ...
# Add any meta tags that may have been missed
os.system(f'exiftool -tagsFromFile {movie} {image}"
Unfortunately, the Geolocation metadata isn't being copied from the .mov file to the .jpg files. exiftool {movie}.mov doesn't list any GPS or Geolocation tags either, but I know that this data is included somewhere within the file as Apple is able to map the location that the 2 second video was taken. Any thoughts as to how I can extract this meta data from Apple's Live Photo .mov clips?
Thanks in advance.
PP
think I found it. The latitude and longitude are there, but then I have to convert that to a City, State,and Country using geopy. Seems to work now
I have been looking for a way to convert a sequence of PNGs to a video. There are ways to do that using the CONCAT function within FFmpeg and using a script.
The problem is that I want to show certain images longer than others. And I need it to be accurate. I can set a duration (in seconds) in the script file. But I need it to be frame-accurate. So far I have not been successful.
This is what I want to make:
Quicktime video with transparancy (Prores4444 or other codec that supports transparancy + alpha channel)
25fps
This is what I have: [ TimecodeIn - TimecodeOut in destination video ]
img001.png [0:00:05:10 - 0:00:07:24]
img002.png [0:00:09:02 - 0:00:12:11]
img003.png [0:00:15:00 - 0:00:17:20]
...
img120.png [0:17:03:11 - 0:17:07:01]
Of course this is not the format of the script file. Just an idea about what kind of data I am dealing with. The PNG-imagefiles are subtitles I generate elsewhere in my application. I would like to be able to export the subtitles as a transparent movie that I can easily import in my video editing software.
I also have been thinking of using blank transparent images I will use as spacers, between the actual subtitle images.
After looking around I think this might help:
On the FFMPEG site they explain about making a timed slideshow
In the Concat demuxer section they talk about making a slideshow, based on a text file, with references to the image files and the duration of the image.
So, I create all the PNG images I need. These images have the subtitle text. Each image holds one subtitle page.
For the moments I want to hide the subtitle, I use a blank PNG.
I generate a text file as explained on the FFMPEG website.
This text file will reference to all the PNGs. For the duration I just calculate the outcue - incue. Easy... I think...
I want to get all of the different images that YouTube stores for all of my videos from my channel Guitar3covers
For a certain video https://www.youtube.com/watch?v=I03uuxgpWd8
the video id is: "I03uuxgpWd8". I can get the same image from both http://img.youtube.com/vi/I03uuxgpWd8/0.jpg
and http://img.youtube.com/vi/I03uuxgpWd8/hqdefault.jpg. I want to get all the images stored by YouTube.
There are actually only 4 different images which is why you are getting the same image. Most are various sizes of 0.jpg, except for 1.jpg, 2.jpg and 3.jpg which are screen caps from different stages of the video.
For reference, YouTube stores 9 thumbnails for each video:
http://img.youtube.com/vi/I03uuxgpWd8/0.jpg (480x360px)
http://img.youtube.com/vi/I03uuxgpWd8/1.jpg (120x90px)
http://img.youtube.com/vi/I03uuxgpWd8/2.jpg (120x90px)
http://img.youtube.com/vi/I03uuxgpWd8/3.jpg (120x90px)
http://img.youtube.com/vi/I03uuxgpWd8/maxresdefault.jpg (1920x1080px)
http://img.youtube.com/vi/I03uuxgpWd8/sddefault.jpg (640x480px)
http://img.youtube.com/vi/I03uuxgpWd8/hqdefault.jpg (480x360px)
http://img.youtube.com/vi/I03uuxgpWd8/mqdefault.jpg (320x180px)
http://img.youtube.com/vi/I03uuxgpWd8/default.jpg (120x90px)
Just replace the video ID (I03uuxgpWd8) for each video. Note that if the video quality is less than the quality of the thumbnail, YouTube will not store an image for that size, so you may need to check for nulls.
For a JPG image, I can just use CGImageSourceCopyPropertiesAtIndex to obtain the various bits of EXIF information from the image. However, this API does not work with quicktime movie files.
What similar Cocoa APIs can I use to extact EXIF information from a Quicktime movie file?
EXIF is a standard for image files, not for movies. There's no EXIF information defined for movies and correspondingly there's no API to retrieve them from quicktime movie files.