I know that there are no blob urls only objects.
I made my own blob object for a video buffer and then I used it in a src of video tag which is something like blob://website.com/blablobbla . I opened this url in the browser it worked
when I opened the url of youtube video src (blob url) into a new tab it did't work but mine video src (blob url) worked
I want to know how can I do the same with my blob urls so that they only work in the src of the html video tag and give error or don't work in the external tab/window of the browsers.I just want to know the technology behind this and blob objects and their url properties.
The question seems somewhat vague to me, so here is what I interpret (also from the code in the fiddle-images in your question):
Blob
(image's binary data) through a XMLHttpRequest()
GET
-request (responseType = 'blob'
)Blob URL
with URL.createObjectURL()
in the URL Store
for XMLHttpRequest()
response
-object (the Blob
holding the binary data)Blob URL
-string as src
for a image (and append the image to the document, thereby showing the image you just downloaded)Blob URL
-string I assume).In your comments you say:
In fiddle I inspected the image and copied the src and then pasted it in new tab and it worked and showed the image I don't want the image to be shown directly with the blob url.
If you go to youtube and open the src of video in new tab : It will not work,, I want this to happen
It appears to me that you do not want the user to be able to view/download the blob when they copy the Blob URL
-string (by examining the live source or simply right-click-on-image>>Copy Imagelocation
) and paste it into a new tab/window (for which you give youtube as an example).
But you are also talking about video's.
TL;DR: It seems your question/bounty might be mixing up 2 different types of URL returned by window.URL.createObjectURL();
:
Blob URL
referencing (objects that represent) 'raw local data' (like (Local-)File, Blob, etc.)Blob URL
from the browser's URL Store
(which you could consider a simplified local webserver inside the browser, only available to that browser).
var myBlobURL=window.URL.createObjectURL(object, flag_oneTimeOnly);
Blob URL
which can be revoked with: window.URL.revokeObjectURL(myBlobURL)
(adds the Blob URL
string to the Revocation List
).flag_oneTimeOnly
which used to revoke the Blob URL
automatically after it's first use, but that is currently no longer part of the spec! Also this flag often didn't work anyway (at least in firefox).var myBlobURL=window.URL.createFor(object);
Blob URL
that is automatically revoked after it's first use.MediaSource object URL
referencing a special MediaSource Objectsrc
of a HTMLMediaElement
(think <audo>
& <video>
elements) to the special MediaSource Object
HTMLMediaElement
window.URL.createObjectURL();
Here's what's happening for the fiddle in your question's image and similar code that downloaded a video as Blob
(where you downloaded the whole video-file's data/binary on the server using an xhr) or any other 'local' data:
You are essentially using the 'bare' 'un-enhanced' File-API.
The URL Store
is only maintained during a session (so it will survive a page-refresh, since it is still the same session) and lost when the document is unloaded.
So, if your fiddle is still open, then fiddle-document (the document that created the Blob URL
) is obviously not yet unloaded, and therefore it's Blob URL
s are available to the browser (any tab/window) as long as it is not revoked!
This is a relevant feature: you can build/download/modify a Blob
in the browser, create a Blob URL
and set it as href
to a file-download link (which the user can right-click and open in a new tab/window!!)
Close the fiddle or revoke the Blob URL
from the URL Store
and the Blob URL
is no longer accessible (also not in a different tab/window).
Try yourself with your modified fiddle: https://jsfiddle.net/7cyoozwv/
In this fiddle it should now no longer be possible to load your sample image into a different tab/window after you copied the image url (once the image is displayed in your page).
Here I revoked the URL manually (revokeObjectURL()
) as it is currently the best cross-browser method (partially due to the api not yet fully being stabilized).
Also note: an element's onload
event can be an elegant place to revoke your Blob URL
.
Here is what's happening to an <audio>
or <video>
source linked to an MediaSource Object
using an MediaSource object URL
returned by window.URL.createObjectURL(MediaSource)
:
The Media Source Extensions (MSE) also extend the File-API
's window.URL.createObjectURL()
to accept a MediaSource Object
. The (current draft of the) URL Object Extension specifies that:
This algorithm is intended to mirror the behavior of the createObjectURL()[FILE-API] method with autoRevoke set to true.
Note that the current spec of the File API
's window.URL.createObjectURL()
no longer has an autoRevoke
(or flag_oneTimeOnly
) boolean flag accessible to the programmer who should be using window.URL.createFor()
for this purpose instead. I wonder when the Media-Source spec will mimic that (and for backward compatibility alias their createObjectURL()
to a new createFor()
extension (seems more appropriate as that is how it seems to be intended to work currently)).
These resulting automatically revoked URL-strings are only intended to link the src
of a HTMLMediaElement
(think <audo>
& <video>
elements) to the special MediaSource Object
.
I don't think that an empty Document
(from a new tab/window) is a <audo>
or <video>
element.
Perhaps "A quick tutorial on MSE"(source: MSDN) might help clarify the difference and basic use:
To use the MSE API, follow these steps:
- Define an HTML5
video
element in the HTML section of a page.- Create a
MediaSource
object in JavaScript.- Create a virtual URL using
createObjectURL
with theMediaSource
object as the source.- Assign the virtual URL to the video element's
src
property.- Create a
SourceBuffer
usingaddSourceBuffer
, with the mime type of the video you're adding.- Get the video initialization segment from the media file online and add it to the
SourceBuffer
withappendBuffer
.- Get the segments of video data from the media file, append them to the
SourceBuffer
withappendBuffer
.- Call the
play
method on the video element.- Repeat step 7 until done.
- Clean up.
You (or a big-time player like youtube who will dynamically select supported technologies for playback on the client's platform (so there is no way to tell for sure what kind of youtube video URL's you are talking about)) could be using the new special MediaSource Object
to play video's (or audio).
This adds buffer-based source options to HTML5 video for streaming support (compared to to downloading a complete video file before playing or use an add-on like Silverlight or Adobe Flash to stream media).
Hope this is what you were after!