Re: Need help related to mkv files.
Dave Rice <[email protected]> Mon, 5 Feb 2018 09:38:00 -0500
| Newsgroups | gmane.comp.multimedia.matroska.devel |
|---|---|
| Message-ID | <[email protected]> |
--===============8318856640615538937== Content-Type: multipart/alternative; boundary="Apple-Mail=_79DB915B-47B8-4DBA-8BF4-CC5CE0136ACA" --Apple-Mail=_79DB915B-47B8-4DBA-8BF4-CC5CE0136ACA Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii Hi, > On Feb 5, 2018, at 5:45 AM, vashu <[email protected]> wrote: >=20 > Hi, >=20 > I hope you are doing well, actually I was doing a research on mkv = files and I had open a mkv file in hex editor. >=20 > I had read the specification given on your site but I'm unable to find = the size of any header. >=20 > As it was given in spec I'm able to find the cluster i.e. = 0x1F,0x43,0xB6,0x75 but can't find the size of a particular cluster. It might be helpful to review the EBML specification. Each Matroska = Element is an EBML Element consisting of 3 parts: Element ID, Element = Data Size, and Element Data. The 0x1F43B675 is the Element ID for the = Cluster. The next byte(s) will be the Element Data Size encoded as a = Variable Integer. I suggest reading = https://tools.ietf.org/html/draft-ietf-cellar-ebml-04#section-6 = <https://tools.ietf.org/html/draft-ietf-cellar-ebml-04#section-6> to = understand how a variable integer is encoded as it will tell you both = the length of the Element Data Size and the value of the Element Data = Size. Best Regards, Dave Rice= --Apple-Mail=_79DB915B-47B8-4DBA-8BF4-CC5CE0136ACA Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=us-ascii <html><head><meta http-equiv=3D"Content-Type" content=3D"text/html = charset=3Dus-ascii"></head><body style=3D"word-wrap: break-word; = -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" = class=3D""><div class=3D"">Hi,</div><br class=3D""><div><blockquote = type=3D"cite" class=3D""><div class=3D"">On Feb 5, 2018, at 5:45 AM, = vashu <<a href=3D"mailto:[email protected]" = class=3D"">[email protected]</a>> wrote:</div><br = class=3D"Apple-interchange-newline"><div class=3D""><div dir=3D"ltr" = class=3D"">Hi,<br class=3D""><br class=3D"">I hope you are doing well, = actually I was doing a research on mkv files and I had open a mkv file = in hex editor.<br class=3D""><br class=3D"">I had read the specification = given on your site but I'm unable to find the size of any header.<br = class=3D""><br class=3D"">As it was given in spec I'm able to find the = cluster i.e. 0x1F,0x43,0xB6,0x75 but can't find the size of a particular = cluster.<br class=3D""></div></div></blockquote><div><br = class=3D""></div><div>It might be helpful to review the EBML = specification. Each Matroska Element is an EBML Element consisting of 3 = parts: Element ID, Element Data Size, and Element Data. The 0x1F43B675 = is the Element ID for the Cluster. The next byte(s) will be the Element = Data Size encoded as a Variable Integer. I suggest reading <a = href=3D"https://tools.ietf.org/html/draft-ietf-cellar-ebml-04#section-6" = class=3D"">https://tools.ietf.org/html/draft-ietf-cellar-ebml-04#section-6= </a> to understand how a variable integer is encoded as it will = tell you both the length of the Element Data Size and the value of the = Element Data Size.</div><div><br class=3D""></div></div>Best = Regards,<div class=3D"">Dave Rice</div></body></html>= --Apple-Mail=_79DB915B-47B8-4DBA-8BF4-CC5CE0136ACA-- --===============8318856640615538937== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KTWF0cm9za2Et ZGV2ZWwgbWFpbGluZyBsaXN0Ck1hdHJvc2thLWRldmVsQGxpc3RzLm1hdHJvc2thLm9yZwpodHRw czovL2xpc3RzLm1hdHJvc2thLm9yZy9jZ2ktYmluL21haWxtYW4vbGlzdGluZm8vbWF0cm9za2Et ZGV2ZWwKUmVhZCBNYXRyb3NrYS1EZXZlbCBvbiBHTWFuZTogaHR0cDovL2Rpci5nbWFuZS5vcmcv Z21hbmUuY29tcC5tdWx0aW1lZGlhLm1hdHJvc2thLmRldmVs --===============8318856640615538937==--