Hm, interesting. You know, in this specific configuration, you don't need a throttle. What happens if you leave it out? It shouldn't change anything, but then, it should work in any case.
Also, you *are* letting the fg terminate itself, right? M On 07/31/2014 04:30 AM, Nguyễn Văn Lý wrote: > Hi Martin, > > Consider the following flow graph. > File Source ------->Throttle --------> Packet Encoder -------> Packet > Decoder --------->File Sink 2 > \ > > \---------------> File Sink 1 > If the File Source loads a small-size image (around 50 kB), then the > Packet Decoder works properly and File Sink 2 can open the image. > However if the File Source load a bigger image or video (9 MB, for > example), then the File Sink 2 achieve only more than 1 MB, and it can > only display a part of the image/video. This surprised me. > > Then I added a File Sink right after the Packet Encoder (it's called > File Sink 1) to see what happened after the Packet Encoder. If I let the > Sample Rate = 32k, then the File Sink 1 receives more than 9 MB, but the > File Sink 2 still receive more than 1 MB. If I let the Sample Rate be > faster, 1M or 4M, then both the File Sink 1 and File Sink 2 only get > more than 1MB. > I wonder if something related to CPU got out of ability with high Sample > Rate or Packet Encoder - Packet Decoder > > Best Regards, > V-L > > Van-Ly Nguyen, > Signals and Systems of Laboratory - SSL > Faculty of Electronics and Telecommunications - FET > University of Engineering and Technology - UET > Vietnam National University, Hanoi - VNU > > Tel: (+84) 978 819 406 > > > > On Wed, Jul 30, 2014 at 9:19 PM, Martin Braun <martin.br...@ettus.com > <mailto:martin.br...@ettus.com>> wrote: > > On 07/30/2014 04:14 PM, Nguyễn Văn Lý wrote: > > Thank you Tom, > > > > I found a note in documentation of the *Packet Encoder *block** > where it > > declares that the *Packet Encoder* is for use with the gnuradio > > modulator blocks: GMSK, DPSK, QAM. I don't know why only these > modulator > > blocks are supported, but not some popular things like BPSK or QPSK. > > Another thing is that my task requires the use of OFDM. > > These should also work (they are basically subsets of QAM), but *you* > have to make sure the absolute phase is correct *before* going into the > packet decoder. > > > Suppose now I have a simple flow graph as below: > > File Source -------> Packet Encoder -------> Packet Decoder ---------> > > File Sink > > I wonder what types of file can be loaded and processed properly > in the > > *File Source* block (text, image, or video ...), and the same question > > for the *File Sink* block :-) > > Any file. The packet blocks really don't care about the contents. > > M > > > > Thank you so much > > Van-Ly > > > > > > Van-Ly Nguyen, > > Signals and Systems of Laboratory - SSL > > Faculty of Electronics and Telecommunications - FET > > University of Engineering and Technology - UET > > Vietnam National University, Hanoi - VNU > > > > Tel: (+84) 978 819 406 > > > > > > > > On Wed, Jul 30, 2014 at 8:24 PM, Tom Rondeau <t...@trondeau.com > <mailto:t...@trondeau.com> > > <mailto:t...@trondeau.com <mailto:t...@trondeau.com>>> wrote: > > > > On Wed, Jul 30, 2014 at 4:44 AM, Nguyễn Văn Lý > > <lynguyenvan....@gmail.com <mailto:lynguyenvan....@gmail.com> > <mailto:lynguyenvan....@gmail.com > <mailto:lynguyenvan....@gmail.com>>> wrote: > > > > Hi all, > > > > Can anyone tell me what do *Packet Encoder* and *Packet > Decoder* > > blocks do? and it would be great if you can give me some > example > > :-) > > Thanks in advance > > > > Van-Ly > > > > > > These are very simple example blocks to show you how to packetize > > data. Packet bytes go in, they get wrapped into a packet of a > given > > payload length with a header, access code, and preamble. The > header > > is just a 2x repetition of the payload length (16 bits for each > > field). Leaving the preamble and access code blank just > chooses the > > defaults. > > > > The decoder just looks for the access code with the number of > > available bits wrong. When it's found, it reads the header to get > > the payload length, extracts the payload, and outputs the payload. > > > > Hope this helps. > > > > Tom > > > > > > > > > > > > _______________________________________________ > > Discuss-gnuradio mailing list > > Discuss-gnuradio@gnu.org <mailto:Discuss-gnuradio@gnu.org> > > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > > > > > _______________________________________________ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org <mailto:Discuss-gnuradio@gnu.org> > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > > _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio