Re: [backstage] What's going on with the News 24 live stream?
On 18/11/2007, Steve Jolly [EMAIL PROTECTED] wrote: Brian Butterworth wrote: Givem the original is at 25fps, why not encode at that in fact? 50fps. ;-) (Pedantic, but important...) If you are going to be pedantic, at least be right! UKTV (and all in Europe) is 25 frames a second I suspect yuou don't understand what interlaced means. S - Sent via the backstage.bbc.co.uk discussion group. To unsubscribe, please visit http://backstage.bbc.co.uk/archives/2005/01/mailing_list.html. Unofficial list archive: http://www.mail-archive.com/backstage@lists.bbc.co.uk/ -- Please email me back if you need any more help. Brian Butterworth http://www.ukfree.tv
Re: [backstage] What's going on with the News 24 live stream?
Martin Deutsch wrote: On Nov 18, 2007 11:43 PM, Steve Jolly [EMAIL PROTECTED] mailto:[EMAIL PROTECTED] wrote: Brian Butterworth wrote: Givem the original is at 25fps, why not encode at that in fact? 50fps. ;-) (Pedantic, but important...) Surely that just depends on whether your f stands for fields or frames? Two fields != one frame. I ranted about this back in August if anyone cares sufficiently... http://elvum.net/web-log/item/18/catid/3 S - Sent via the backstage.bbc.co.uk discussion group. To unsubscribe, please visit http://backstage.bbc.co.uk/archives/2005/01/mailing_list.html. Unofficial list archive: http://www.mail-archive.com/backstage@lists.bbc.co.uk/
Re: [backstage] What's going on with the News 24 live stream?
On 11/19/07, Christopher Woods [EMAIL PROTECTED] wrote: Ha :D Anyway, the cameras they were using had the holographic BBC HD logo plastered along the side of them, so things are looking up - unless they're just old skool SD cameras with a chavlike shopping list down the side of them! I wonder if the N24 cameras are similarly upgraded... It'd be nice to know that it's being filmed progressively, even if it's converted to interlaced for the final step, something which can always change in the future. Only a couple of TVC's studios have been upgraded to HD - TC1 (the really big one, often home to Strictly Come Dancing and Later with Jools) and TC8 (used for light ents stuff like Two Pints). From what I've read, News 24 might well be using the same studio cameras as they did when they opened - plus its source material is almost entirely SD, so there wouldn't be much point in upgrading the channel to HD just yet. (As an aside, BBC Scotland's new studios are all HD - you can watch the studio parts of Reporting Scotland in glorious 1080i, but only in the gallery and one or two other places in the BBC.) - martin
Re: [backstage] What's going on with the News 24 live stream?
Christopher Woods wrote: Anyway, the cameras they were using had the holographic BBC HD logo plastered along the side of them, so things are looking up - unless they're just old skool SD cameras with a chavlike shopping list down the side of them! I wonder if the N24 cameras are similarly upgraded... It'd be nice to know that it's being filmed progressively, even if it's converted to interlaced for the final step, something which can always change in the future. The BBC's announced plans to shift all production to HD by 2010 (http://news.bbc.co.uk/newswatch/ukfs/hi/newsid_473/newsid_4739000/4739094.stm), but it's not there yet. Don't assume that HD==progressive, incidentally - despite the fact that humankind has developed far better lossy compression mechanisms than interlace over the years, interlace still made it into the HD standards documents... S - Sent via the backstage.bbc.co.uk discussion group. To unsubscribe, please visit http://backstage.bbc.co.uk/archives/2005/01/mailing_list.html. Unofficial list archive: http://www.mail-archive.com/backstage@lists.bbc.co.uk/
Re: [backstage] What's going on with the News 24 live stream?
Brian Butterworth wrote: If you are going to be pedantic, at least be right! UKTV (and all in Europe) is 25 frames a second I suspect yuou don't understand what interlaced means. I think I detect an impending semantic argument, so let me try and avoid it. You're (I think) defining a frame to be the combination of as many sequential scans of an image (fields) as are required to build up a full-resolution two-dimensional picture. Two fields per frame, in the present case. Let me expand slightly: fields are often bundled together and called frames for broadcast purposes, although not necessarily in such a way that they form a combined image (eg two fields may be placed one above the other to form a frame for some MPEG treatments of interlaced material). Because of this, yes, you can describe 50 fields-per-second television as 25 frames-per-second. I would like to argue, however, that it is misleading to characterise an interlaced television system in terms of its frame rate. Why? Because each field comes from a different point in time, and combining them together leads to spatial (combing) and temporal (judder) artefacts. (There are exceptions to this rule, eg when each frame of a film is broadcast as two successive fields - in this case simple recombination of the fields does not necessarily result in these artefacts.) S - Sent via the backstage.bbc.co.uk discussion group. To unsubscribe, please visit http://backstage.bbc.co.uk/archives/2005/01/mailing_list.html. Unofficial list archive: http://www.mail-archive.com/backstage@lists.bbc.co.uk/
Re: [backstage] What's going on with the News 24 live stream?
Steve, I was working from the assumption about the ~30fps comment that this was about frames not fields. All SD UK TV is interlaced, with the exeption of telecinied content. NTSC content runs at 29.97fps, to stop strobing effects on the screen when near lightbulbs on the US 30Hz mains. On 19/11/2007, Steve Jolly [EMAIL PROTECTED] wrote: Brian Butterworth wrote: If you are going to be pedantic, at least be right! UKTV (and all in Europe) is 25 frames a second I suspect yuou don't understand what interlaced means. I think I detect an impending semantic argument, so let me try and avoid it. You're (I think) defining a frame to be the combination of as many sequential scans of an image (fields) as are required to build up a full-resolution two-dimensional picture. Two fields per frame, in the present case. Let me expand slightly: fields are often bundled together and called frames for broadcast purposes, although not necessarily in such a way that they form a combined image (eg two fields may be placed one above the other to form a frame for some MPEG treatments of interlaced material). Because of this, yes, you can describe 50 fields-per-second television as 25 frames-per-second. I would like to argue, however, that it is misleading to characterise an interlaced television system in terms of its frame rate. Why? Because each field comes from a different point in time, and combining them together leads to spatial (combing) and temporal (judder) artefacts. (There are exceptions to this rule, eg when each frame of a film is broadcast as two successive fields - in this case simple recombination of the fields does not necessarily result in these artefacts.) S - Sent via the backstage.bbc.co.uk discussion group. To unsubscribe, please visit http://backstage.bbc.co.uk/archives/2005/01/mailing_list.html. Unofficial list archive: http://www.mail-archive.com/backstage@lists.bbc.co.uk/ -- Please email me back if you need any more help. Brian Butterworth http://www.ukfree.tv
RE: [backstage] What's going on with the News 24 live stream?
Indeed Brian, I've been an iPlayer user since they opened up the second private beta a few months ago. I'd heard rumblings that all the BBC channels would eventually be streamed via the iPlayer interface though - can't confirm that though because I don't know who to ask either way. Maybe I should've collared Cridland at SBES on Thursday but I didn't think he'd appreciate it. ;) 25fps would be preferable, of course!
Re: [backstage] What's going on with the News 24 live stream?
Brian Butterworth wrote: Givem the original is at 25fps, why not encode at that in fact? 50fps. ;-) (Pedantic, but important...) S - Sent via the backstage.bbc.co.uk discussion group. To unsubscribe, please visit http://backstage.bbc.co.uk/archives/2005/01/mailing_list.html. Unofficial list archive: http://www.mail-archive.com/backstage@lists.bbc.co.uk/
Re: [backstage] What's going on with the News 24 live stream?
On Nov 18, 2007 11:43 PM, Steve Jolly [EMAIL PROTECTED] wrote: Brian Butterworth wrote: Givem the original is at 25fps, why not encode at that in fact? 50fps. ;-) (Pedantic, but important...) Surely that just depends on whether your f stands for fields or frames? - martin
RE: [backstage] What's going on with the News 24 live stream?
Ha :D I went to a Two Pints filming a couple of Sundays ago (at TV Centre), it's a real shame the 'wardens' almost bit my head off at the sight of my camera, I was told twice I couldn't take any photos at all :( even though people with instant cameras and smaller ones were taking loads of photos unhindered before the performance started. Anyway, the cameras they were using had the holographic BBC HD logo plastered along the side of them, so things are looking up - unless they're just old skool SD cameras with a chavlike shopping list down the side of them! I wonder if the N24 cameras are similarly upgraded... It'd be nice to know that it's being filmed progressively, even if it's converted to interlaced for the final step, something which can always change in the future. _ From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Martin Deutsch Sent: 19 November 2007 00:55 To: backstage@lists.bbc.co.uk Subject: Re: [backstage] What's going on with the News 24 live stream? On Nov 18, 2007 11:43 PM, Steve Jolly [EMAIL PROTECTED] wrote: Brian Butterworth wrote: Givem the original is at 25fps, why not encode at that in fact? 50fps. ;-) (Pedantic, but important...) Surely that just depends on whether your f stands for fields or frames? - martin
[backstage] What's going on with the News 24 live stream?
I've noticed for a few weeks now that the BBC news stream has really gone down in quality. It looks overexposed and awfully washed out; prior to this it looked great, just like a pure digital feed should. Also, the stream is apparently being encoded at 29fps (according to WMP) but it's playing back at 23.9/24fps - why not encode at 24fps? Surely it's wasting bits, even if the perceived fps is incorrect and the actual fps is correct... But there's still no reason for this incorrect setup. The odd 400x224 resolution is puzzling too, but better than nothing - as is the (dismal) 32 whole kilobits per second of bandwidth devoted to the audio stream. Is there ever going to be a decent high quality stream of N24 available via the web site (or maybe be rolled out with a future incarnation of iPlayer?) Either way, I'd still appreciate it if some attention was paid to the N24 stream, so if someone's reading this who knows someone who can get someone else to take a look, that'd be great! Christopher
Re: [backstage] What's going on with the News 24 live stream?
On 18/11/2007, Christopher Woods [EMAIL PROTECTED] wrote: I've noticed for a few weeks now that the BBC news stream has really gone down in quality. It looks overexposed and awfully washed out; prior to this it looked great, just like a pure digital feed should. Also, the stream is apparently being encoded at 29fps (according to WMP) but it's playing back at 23.9/24fps - why not encode at 24fps? Surely it's wasting bits, even if the perceived fps is incorrect and the actual fps is correct... But there's still no reason for this incorrect setup. Givem the original is at 25fps, why not encode at that in fact? The odd 400x224 resolution is puzzling too, but better than nothing - as is the (dismal) 32 whole kilobits per second of bandwidth devoted to the audio stream. Is there ever going to be a decent high quality stream of N24 available via the web site (or maybe be rolled out with a future incarnation of iPlayer?) iPlayer is a peer-to-peer downloadsystem. If you want another steaming option, try http://www.livestation.com/ N24 is mono and low-bitrate on Freeview as well. Either way, I'd still appreciate it if some attention was paid to the N24 stream, so if someone's reading this who knows someone who can get someone else to take a look, that'd be great! Christopher -- Please email me back if you need any more help. Brian Butterworth www.ukfree.tv
