zbar

zbar

Properties

gboolean message Read / Write
gboolean cache Read / Write
gboolean attach-frame Read / Write

Types and Values

struct GstZBar

Description

Detect bar codes in the video streams and send them as element messages to the GstBus if .“message” property is TRUE. If the .“attach-frame” property is TRUE, the posted barcode message includes a sample of the frame where the barcode was detected (Since 1.6).

The element generate messages namedbarcode. The structure containes these fields:

  • GstClockTime timestamp: the timestamp of the buffer that triggered the message.

  • gchar * type: the symbol type.

  • gchar * symbol: the deteted bar code data.

  • gint quality: an unscaled, relative quantity: larger values are better than smaller values.

  • GstSample frame: the frame in which the barcode message was detected, if the .“attach-frame” property was set to TRUE (Since 1.6)

Example launch lines

1
gst-launch-1.0 -m v4l2src ! videoconvert ! zbar ! videoconvert ! xvimagesink

This pipeline will detect barcodes and send them as messages.

1
gst-launch-1.0 -m v4l2src ! tee name=t ! queue ! videoconvert ! zbar ! fakesink t. ! queue ! xvimagesink

Same as above, but running the filter on a branch to keep the display in color

Synopsis

Element Information

plugin

zbar

author

Stefan Kost <ensonic@users.sf.net>

class

Filter/Analyzer/Video

Element Pads

name

sink

direction

sink

presence

always

details

video/x-raw, format=(string){ Y800, I420, YV12, NV12, NV21, Y41B, Y42B, YUV9, YVU9 }, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]

name

src

direction

source

presence

always

details

video/x-raw, format=(string){ Y800, I420, YV12, NV12, NV21, Y41B, Y42B, YUV9, YVU9 }, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]

Functions

Types and Values

struct GstZBar

struct GstZBar {
};

Opaque data structure.

Property Details

The “message” property

  “message”                  gboolean

Post a barcode message for each detected code.

Flags: Read / Write

Default value: TRUE


The “cache” property

  “cache”                    gboolean

Enable or disable the inter-image result cache.

Flags: Read / Write

Default value: FALSE


The “attach-frame” property

  “attach-frame”             gboolean

Attach a frame dump to each barcode message.

Flags: Read / Write

Default value: FALSE