diff options
author | Tom Rondeau | 2012-12-14 16:10:30 -0500 |
---|---|---|
committer | Tom Rondeau | 2012-12-14 17:11:40 -0500 |
commit | 461ece56b36a44b2405282630157739c7f9a26ba (patch) | |
tree | c5b1a484a43a35324e1ea1beae7652aa80da5d83 /docs/doxygen/other/metadata.dox | |
parent | 8e8ed231cd2469e1a39c5ae6af23ac9b29264af7 (diff) | |
download | gnuradio-461ece56b36a44b2405282630157739c7f9a26ba.tar.gz gnuradio-461ece56b36a44b2405282630157739c7f9a26ba.tar.bz2 gnuradio-461ece56b36a44b2405282630157739c7f9a26ba.zip |
blocks: moving file metadata sink/source to gr-blocks.
Diffstat (limited to 'docs/doxygen/other/metadata.dox')
-rw-r--r-- | docs/doxygen/other/metadata.dox | 32 |
1 files changed, 19 insertions, 13 deletions
diff --git a/docs/doxygen/other/metadata.dox b/docs/doxygen/other/metadata.dox index 1b3c891a8..9fad7c584 100644 --- a/docs/doxygen/other/metadata.dox +++ b/docs/doxygen/other/metadata.dox @@ -9,8 +9,8 @@ the system state such as sample rate or if a receiver's frequency are not conveyed with the data in the file itself. Header of metadata solve this problem. -We write metadata files using gr_file_meta_sink and read metadata -files using gr_file_meta_source. +We write metadata files using blocks::file_meta_sink and read metadata +files using blocks::file_meta_source. Metadata files have headers that carry information about a segment of data within the file. The header structure is described in detail in @@ -88,12 +88,12 @@ keep the sample times exact. \subsection implementation Implementation -Metadata files are created using gr_file_meta_sink. The default +Metadata files are created using file_meta_sink. The default behavior is to create a single file with inline headers as metadata. An option can be set to switch to detached header mode. Metadata file are read into a flowgraph using -gr_file_meta_source. This source reads a metadata file, inline by +file_meta_source. This source reads a metadata file, inline by default with a settable option to use detached headers. The data from the segments is converted into a standard streaming output. The 'rx_rate' and 'rx_time' and all key:value pairs in the extra header @@ -250,13 +250,13 @@ manipulating metadata files. There is a general parser in Python that will convert the PMT header and extra header into Python dictionaries. This utility is: -- gnuradio-core/src/python/gnuradio/parse_file_metadata.py +- gr-blocks/python/parse_file_metadata.py This program is installed into the Python directory under the 'gnuradio' module, so it can be accessed with: \code -from gnuradio import parse_file_metadata +from gnuradio.blocks import parse_file_metadata \endcode It defines HEADER_LENGTH as the static length of the metadata header @@ -284,12 +284,14 @@ data with '.hdr' appended to it. Examples are located in: -- gnuradio-core/src/examples/metadata +- gr-blocks/examples/metadata -Currently, there are two GRC example programs. +Currently, there are a few GRC example programs. - file_metadata_sink: create a metadata file from UHD samples. - file_metadata_source: read the metadata file as input to a simple graph. +- file_metadata_vector_sink: create a metadata file from UHD samples. +- file_metadata_vector_source: read the metadata file as input to a simple graph. The file sink example can be switched to use a signal source instead of a UHD source, but no extra tagged data is used in this mode. @@ -298,6 +300,9 @@ The file source example pushes the data stream to a new raw file while a tag debugger block prints out any tags observed in the metedata file. A QT GUI time sink is used to look at the signal as well. +The versions with 'vector' in the name are similar except they use +vectors of data. + The following shows a simple way of creating extra metadata for a metadata file. This example is just showing how we can insert a date into the metadata to keep track of later. The date in this case is @@ -305,6 +310,7 @@ encoded as a vector of uint16 with [day, month, year]. \code from gruel import pmt + from gnuradio import blocks key = pmt.pmt_intern("date") val = pmt.pmt_init_u16vector(3, [13,12,2012]) @@ -312,11 +318,11 @@ encoded as a vector of uint16 with [day, month, year]. extras = pmt.pmt_make_dict() extras = pmt.pmt_dict_add(extras, key, val) extras_str = pmt.pmt_serialize_str(extras) - self.sink = gr.file_meta_sink(gr.sizeof_gr_complex, - "/tmp/metadat_file.out", - samp_rate, 1, - gr.GR_FILE_FLOAT, True, - 1000000, extra_str, False) + self.sink = blocks.file_meta_sink(gr.sizeof_gr_complex, + "/tmp/metadat_file.out", + samp_rate, 1, + blocks.GR_FILE_FLOAT, True, + 1000000, extra_str, False) \endcode |