movie_publisher

This package contains several tools for using movie files in ROS (playback, conversion to bag files etc.).

It handles any file formats the system installation of ffmpeg can decode.

Important: This package is meant to work with moviepy. However, due to packaging issues, moviepy cannot be installed automatically as a dependency. There’s a fallback using OpenCV, which is however worse. Please, install moviepy manually calling:

sudo pip install moviepy

or

rosdep install python-moviepy-pip

Main tools

• movie_publisher_node: A ROS node that serves a video file as video topic source (sensor_msgs/Image and friends).
• movie_publisher.launch: A launch file for convenient usage of the node. It also allows starting an image_transport/republish node that converts the video stream from raw to compressed/theora. In the immediate mode, it can also be used to convert video files to bagfiles in a batch.
• movie_to_bag: A batch script that takes a video as input and transforms it into a bag file.
• add_movie_to_bag: A batch script that adds a video as a topic into an existing bag file.

Helper tools

• fix_bag_timestamps: A batch script that rewrites bag files so that the message publication time is taken from the message header. This allows you to generate bagfile data at high speed and then reprocess them to have more suitable publication timestamps.
• merge.py: A copy of srv_tools/merge.py which is not available in indigo.

movie_publisher_node

The node can run with either of two backends - moviepy and opencv. moviepy is strongly recommended, as it uses ffmpeg, which is quite versatile and efficient. Is you do not set the backend param, autodetection is run.

Published topics

• movie (sensor_msgs/Image): The published movie, in raw format.

Node-private parameters:

• movie_file (string, required): Path to the movie to play. Any format that ffmpeg can decode.
• fps (float, optional): If set, the playback will be at the specified FPS (speeding up/slowing down the movie).
• start (float|tuple|string, optional): If set, playback will start from the specified time. Can be expressed in seconds (15.35), in (min, sec), in (hour, min, sec), or as a string: '01:03:05.35'. Cannot be set together with end and duration.
• end (float|tuple|string, optional): If set, playback will stop at the specified time (not affected by start). Can be expressed in seconds (15.35), in (min, sec), in (hour, min, sec), or as a string: '01:03:05.35'. Cannot be set together with start and duration.
• duration (float|tuple|string, optional): If set, playback will have this duration. If end is also set, the duration is counted from the end of the clip, otherwise, it is the duration from the start of the clip. Can be expressed in seconds (15.35), in (min, sec), in (hour, min, sec), or as a string: '01:03:05.35'. Cannot be set together with start and end.
• loop (bool, default False): Whether to loop the movie until the node is shut down. Exludes immediate.
• immediate (bool, default False): If True, the movie will be processed and published as quickly as possible not waiting for the real time. The timestamps in the resulting messages act “real-world-like” (i.e. 15 FPS means the frames’ timestamps will be 1/15 sec apart). You can set fake_time_start if you want these timestamps to begin from a non-zero time. Excludes loop.
• playback_rate (float, optional): If set to a number, immediate mode will not play as fast as possible, but at this rate (set the rate to a number where you do not lose any messages, e.g. in image_transport/republish).
• fake_time_start (float, default 0.0): Used with immediate to specify the timestamp of the first message.
• frame_id (string, default “”): The frame_id used in the messages’ headers.
• spin_after_end (bool, default False): If True, a rospy.spin() is called after the movie has been published.
• verbose (bool, default False): If True, logs info about every frame played.
• wait_after_publisher_created (float, default 1.0): A workaround for the case where you need to give your subscribers some time after the publisher was created. Tweak this number until you get no missing start messages.
• publisher_queue_size (int, default 1000 in immediate mode, 10 otherwise): queue_size of the movie publisher.
• backend (string, default “moviepy”): The backend to use for reading video. Either moviepy or opencv. If moviepy is selected and not found, opencv will be used (which might support less codecs).
• ffmpeg (string, default “”): If nonempty, specifies the (absolute) path to the ffmpeg binary to use.

movie_publisher.launch

This launch file takes arguments with the same name as the node’s parameters.

Additionally, it takes these arguments:

• transport (string, default 'raw'): Type of the image transport. The launch file will start up an image_transport/republish node that publishes the video encoded to this transport type.
• republished_topic_basename (string, default movie_$(arg transport)): Base name of the topic that will serve the republished messages. Full name of the topic will be $(arg republished_topic_basename)/$(arg transport) (or $(arg republished_topic_basename) in case of raw transport). The base name cannot be the same as the topic the movie_publisher_node subscribes to (movie by default).

movie_to_bag

Convert a movie file to a bag file with video topic.

It is a Bash script with ROS node-like API - you pass it parameters via _param:=value on commandline or via ROS param server.

Node-private parameters:

• movie (string): Path to the source movie file.
• bag (string): Path where the result should be stored.
• topic (string): name of the movie’s topic in the bag file
• overwrite_bag (bool, default false): If true, overwrites existing bag file, otherwise exits with error if bag exists.
• tmp_bag (string, default /tmp/movie.bag): Path where a temporary bag file might be stored.
• transport (string, default compressed): Name of the image transport to use for encoding the image. Either raw, compressed, theora or any other installed image transport.

Usage

Call this script from commandline setting the node-private parameters, and pass any other arg:=value arguments - these will be relayed to movie_publisher.launch as is. Do not pass arguments that would collide with the node-private parameters of this script (e.g. movie_file).

Example:

rosrun movie_publisher movie_to_bag _movie:=movie.mp4 _bag:=movie.bag _topic:="/movie" start:=5 fake_time_start:=1548323340.24

add_movie_to_bag

Add a movie file to an existing bagfile as a topic.

It is a Bash script with ROS node-like API - you pass it parameters via _param:=value on commandline or via ROS param server.

Node-private parameters:

• movie (string): Path to the source movie file.
• bag_in (string): Path to the source bag file.
• bag_out (string, default: output.bag): Path where the result should be stored.
• topic (string): Name of the movie’s topic in the bag file.
• movie_delay (int, default 0): Delay (in seconds) of the movie file from the bag file start. May be negative.
• overwrite_out_bag (bool, default false): If true, overwrites existing bag_out file, otherwise exits with error if bag_out exists.
• bag_tmp (string, default /tmp/movie_add_to.bag): Path where a temporary bag file might be stored.
• transport (string, default compressed): Name of the image transport to use for encoding the image. Either raw, compressed, theora or any other installed image transport.

Usage

Call this script from commandline setting the node-private parameters, and pass any other arg:=value arguments - these will be relayed to movie_publisher.launch as is. Do not pass arguments that would collide with the node-private parameters of this script (e.g. movie_file).

Example:

rosrun movie_publisher add_movie_to_bag _movie:=movie.mp4 _bag_in:=movie_in.bag _bag_out:=movie_out.bag _topic:="/movie" start:=5 movie_delay:=-1

fix_bag_timestamps

Goes through in_bag and for all messages with a header field sets their publication time to the time stored in their header.stamp plus delay. If topics are set, only works on messages on the listed topics. Reading timestamps from /tf is also supported.

It is a Python script with ROS node-like API - you pass it parameters via _param:=value on commandline.

Node-private parameters:

• in_bag (string): Path to the source bag file.
• out_bag (string): Path where the result should be stored.
• topics (string, default: ''): If nonempty, rewrite only timestamps of the listed topics. Pass a comma-separated list of topics.
• delay (int, default 0): Delay (in seconds) which is added to the timestamp read from header. May be negative.
• overwrite_existing (bool, default false): If true, overwrites existing out_bag file, otherwise exits with error if out_bag exists.