What is the bitrate of Dish HD shows?
- Thread starter sofakng
- Start date
- Latest activity Latest activity:
- Replies 10
- Views 7K
Thanks!
Is there an average number? (eg. 10 Mbps versus OTA which is... 20-30?)
...or is there a min/max? I understand that at certain times if the signal is horrible that it may drop to a very, very low number but is there some kind of average?
Also, are there any charts for the resolution used on the different channels?
Is there an average number? (eg. 10 Mbps versus OTA which is... 20-30?)
...or is there a min/max? I understand that at certain times if the signal is horrible that it may drop to a very, very low number but is there some kind of average?
Also, are there any charts for the resolution used on the different channels?
Bitrate will also vary depending on the compression being used for the channel (MPEG-2 vs MPEG-4).
Not really. It depends upon so many factors, including the source material itself. Material with little motion in it can tolerate higher rates of compression without degradation than can action scenes.
I believe under ATSC the OTA bitrate is 19 Mbps. Tops. If they're multi-casting, each channel/subchannel will be less, but the total cannot exceed 19. I believe the bitrate on dvd is less than 10. Total bitrate (video + audio) on Blu-rays gets into the 40s, but is often not much more than half that.
On edit, from Blu-ray.com:
How fast can you read/write data on a Blu-ray disc?
According to the Blu-ray Disc specification, 1x speed is defined as 36Mbps. However, as BD-ROM movies will require a 54Mbps data transfer rate the minimum speed we're expecting to see is 2x (72Mbps). Blu-ray also has the potential for much higher speeds, as a result of the larger numerical aperture (NA) adopted by Blu-ray Disc. The large NA value effectively means that Blu-ray will require less recording power and lower disc rotation speed than DVD and HD-DVD to achieve the same data transfer rate. While the media itself limited the recording speed in the past, the only limiting factor for Blu-ray is the capacity of the hardware. If we assume a maximum disc rotation speed of 10,000 RPM, then 12x at the outer diameter should be possible (about 400Mbps). This is why the Blu-ray Disc Association (BDA) already has plans to raise the speed to 8x (288Mbps) or more in the future.
I believe under ATSC the OTA bitrate is 19 Mbps. Tops. If they're multi-casting, each channel/subchannel will be less, but the total cannot exceed 19. I believe the bitrate on dvd is less than 10. Total bitrate (video + audio) on Blu-rays gets into the 40s, but is often not much more than half that.
On edit, from Blu-ray.com:
How fast can you read/write data on a Blu-ray disc?
According to the Blu-ray Disc specification, 1x speed is defined as 36Mbps. However, as BD-ROM movies will require a 54Mbps data transfer rate the minimum speed we're expecting to see is 2x (72Mbps). Blu-ray also has the potential for much higher speeds, as a result of the larger numerical aperture (NA) adopted by Blu-ray Disc. The large NA value effectively means that Blu-ray will require less recording power and lower disc rotation speed than DVD and HD-DVD to achieve the same data transfer rate. While the media itself limited the recording speed in the past, the only limiting factor for Blu-ray is the capacity of the hardware. If we assume a maximum disc rotation speed of 10,000 RPM, then 12x at the outer diameter should be possible (about 400Mbps). This is why the Blu-ray Disc Association (BDA) already has plans to raise the speed to 8x (288Mbps) or more in the future.
Last edited:
According to Engadget HBO HD Mpeg4 streams at 8 Mbps and mandates that carries can not lower quality.
HBO to use MPEG-4 and mandate a minimum bit-rate - Engadget HD
HBO to use MPEG-4 and mandate a minimum bit-rate - Engadget HD
Not so long ago Digi posted the bitstream for one transponder with MPEG4 channels. The average bitrate was 6-8 Mbps.
I don't know what SD QAM signals are like, but I know OTA ATSC signals have a 702X480 resolution that's (obviously) pretty close to DVD in quality. Dish SD signals are only 544X480.
Also the type of programming places different pressures on the image. While a full 19.4Mbps
is needed for a sporting event, only 6Mbps may be required for a movie in MPEG2. Moving to MPEG 4 increases efficiencies over MPEG2. I remember the brains at Quvis (Digital cinema folks) claiming a full 24Mbps signal with no visual loss at 6Mbps. Some of their codec is used in MPEG4 2.64. In other words, don't put all your belief of image quality based on data rates alone.
is needed for a sporting event, only 6Mbps may be required for a movie in MPEG2. Moving to MPEG 4 increases efficiencies over MPEG2. I remember the brains at Quvis (Digital cinema folks) claiming a full 24Mbps signal with no visual loss at 6Mbps. Some of their codec is used in MPEG4 2.64. In other words, don't put all your belief of image quality based on data rates alone.
