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Diffstat (limited to 'thumbnailer/shotwell-video-thumbnailer.vala')
-rw-r--r-- | thumbnailer/shotwell-video-thumbnailer.vala | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/thumbnailer/shotwell-video-thumbnailer.vala b/thumbnailer/shotwell-video-thumbnailer.vala new file mode 100644 index 0000000..5b8b89a --- /dev/null +++ b/thumbnailer/shotwell-video-thumbnailer.vala @@ -0,0 +1,133 @@ +/* Copyright 2011-2014 Yorba Foundation + * + * This is a Vala-rewrite of GStreamer snapshot example. Adapted from earlier + * work from Wim Taymans. + * + * This software is licensed under the GNU LGPL (version 2.1 or later). + * See the COPYING file in this distribution. + */ + +// Shotwell Thumbnailer takes in a video file and returns a thumbnail to stdout. This is +// a replacement for totem-video-thumbnailer +class ShotwellThumbnailer { + const string caps_string = """video/x-raw,format=RGB,pixel-aspect-ratio=1/1"""; + + public static int main(string[] args) { + Gst.Element pipeline, sink; + int width, height; + Gst.Sample sample; + string descr; + Gdk.Pixbuf pixbuf; + int64 duration, position; + Gst.StateChangeReturn ret; + bool res; + + Gst.init(ref args); + + if (args.length != 2) { + stdout.printf("usage: %s [filename]\n Writes video thumbnail to stdout\n", args[0]); + return 1; + } + + descr = "filesrc location=\"%s\" ! decodebin ! videoconvert ! videoscale ! ".printf(args[1]) + + "appsink name=sink caps=\"%s\"".printf(caps_string); + + try { + // Create new pipeline. + pipeline = Gst.parse_launch(descr); + + // Get sink. + sink = ((Gst.Bin) pipeline).get_by_name("sink"); + + // Set to PAUSED to make the first frame arrive in the sink. + ret = pipeline.set_state(Gst.State.PAUSED); + if (ret == Gst.StateChangeReturn.FAILURE) { + stderr.printf("Failed to play the file: couldn't set state\n"); + return 3; + } else if (ret == Gst.StateChangeReturn.NO_PREROLL) { + stderr.printf("Live sources not supported yet.\n"); + return 4; + } + + // This can block for up to 5 seconds. If your machine is really overloaded, + // it might time out before the pipeline prerolled and we generate an error. A + // better way is to run a mainloop and catch errors there. + ret = pipeline.get_state(null, null, 5 * Gst.SECOND); + if (ret == Gst.StateChangeReturn.FAILURE) { + stderr.printf("Failed to play the file: couldn't get state.\n"); + return 3; + } + + /* get the duration */ + pipeline.query_duration (Gst.Format.TIME, out duration); + + position = 1 * Gst.SECOND; + + /* seek to the a position in the file. Most files have a black first frame so + * by seeking to somewhere else we have a bigger chance of getting something + * more interesting. An optimisation would be to detect black images and then + * seek a little more */ + pipeline.seek_simple (Gst.Format.TIME, Gst.SeekFlags.KEY_UNIT | Gst.SeekFlags.FLUSH, position); + + /* get the preroll buffer from appsink, this block untils appsink really + * prerolls */ + GLib.Signal.emit_by_name (sink, "pull-preroll", out sample, null); + + // if we have a buffer now, convert it to a pixbuf. It's possible that we + // don't have a buffer because we went EOS right away or had an error. + if (sample != null) { + Gst.Buffer buffer; + Gst.Caps caps; + unowned Gst.Structure s; + Gst.MapInfo mapinfo; + uint8[]? pngdata; + + // Get the snapshot buffer format now. We set the caps on the appsink so + // that it can only be an rgb buffer. The only thing we have not specified + // on the caps is the height, which is dependent on the pixel-aspect-ratio + // of the source material. + caps = sample.get_caps(); + if (caps == null) { + stderr.printf("could not get snapshot format\n"); + return 5; + } + + s = caps.get_structure(0); + + // We need to get the final caps on the buffer to get the size. + res = s.get_int("width", out width); + res |= s.get_int("height", out height); + if (!res) { + stderr.printf("Could not get snapshot dimension\n"); + return 6; + } + + buffer = sample.get_buffer(); + buffer.map(out mapinfo, Gst.MapFlags.READ); + + // Create pixmap from buffer and save, gstreamer video buffers have a stride + // that is rounded up to the nearest multiple of 4. + pixbuf = new Gdk.Pixbuf.from_data(mapinfo.data, Gdk.Colorspace.RGB, false, 8, + width, height, (((width * 3)+3)&~3), null); + + // Save the pixbuf. + pixbuf.save_to_buffer(out pngdata, "png"); + stdout.write(pngdata); + buffer.unmap(mapinfo); + } else { + stderr.printf("Could not make snapshot\n"); + return 10; + } + + // cleanup and exit. + pipeline.set_state(Gst.State.NULL); + + } catch (Error e) { + stderr.printf(e.message); + return 2; + } + + return 0; + } +} + |