On 01/01/2013 06:48 PM, Manu Abraham wrote:
On Tue, Jan 1, 2013 at 8:30 PM, Mauro Carvalho Chehab <mchehab@xxxxxxxxxx> wrote:[RFCv4] dvb: Add DVBv5 properties for quality parameters The DVBv3 quality parameters are limited on several ways: - Doesn't provide any way to indicate the used measure; - Userspace need to guess how to calculate the measure; - Only a limited set of stats are supported; - Doesn't provide QoS measure for the OFDM TPS/TMCC carriers, used to detect the network parameters for DVB-T/ISDB-T; - Can't be called in a way to require them to be filled all at once (atomic reads from the hardware), with may cause troubles on interpreting them on userspace; - On some OFDM delivery systems, the carriers can be independently modulated, having different properties. Currently, there's no way to report per-layer stats;per layer stats is a mythical bird, nothing of that sort does exist. If some driver states that it is simply due to lack of knowledge at the coding side. ISDB-T uses hierarchial modulation, just like DVB-S2 or DVB-T2
Manu, you confused now two concept (which are aimed to resolve same real life problem) - hierarchical coding and multiple transport stream. Both are quite similar on lower level of radio channel, but differs on upper levels.
Hierarchical is a little bit weird baby as it remuxes those lower lever radio channels (called layers in case of ISDB-T) to one single mux! There is only single TS which demodulator is responsible to remux all those 3 physical "layer" channels, which could be modulated differently. So after demodulation you really has a TS which contains stream that has different statistics. That's opposite to compared for multiple TS principle used for DVB-T2/S2. In case of multiple TS you have same statistics for whole TS (but naturally there could be multiple TS after demodulation).
regards Antti -- http://palosaari.fi/ -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
