lazy-player/lazy_player/thumbnailer.py

117 lines
3.1 KiB
Python

from __future__ import annotations
import threading
from queue import Empty, Queue
from gi.repository import Gst
from .file_model import FileItem
class Thumbnailer(threading.Thread):
queue: Queue[FileItem | None]
def __init__(self):
super().__init__(daemon=True)
self.queue = Queue(maxsize=1)
def generate_thumbnail(self, file_item: FileItem):
"""Add a file item to the thumbnail queue"""
if not file_item.full_path.is_file():
return
# Replace any pending item in the queue
try:
self.queue.get_nowait()
except Empty:
pass
self.queue.put_nowait(file_item)
def stop(self):
"""Stop the thumbnailer thread"""
# Replace any pending items in the queue
try:
self.queue.get_nowait()
except Empty:
pass
self.queue.put_nowait(None)
self.join()
def run(self) -> None:
"""Process items from the queue continuously"""
while True:
file_item = self.queue.get(block=True)
if file_item is None:
break
self._generate_thumbnail(file_item)
def _generate_thumbnail(self, file_item: FileItem):
"""Generate thumbnail for a single file"""
pipeline_str = (
"uridecodebin name=uridecodebin ! "
"videoconvert ! "
"jpegenc quality=85 ! "
"appsink name=sink"
)
pipeline = Gst.parse_launch(pipeline_str)
assert isinstance(pipeline, Gst.Pipeline)
sink = pipeline.get_by_name("sink")
assert isinstance(sink, Gst.Element)
uridecodebin = pipeline.get_by_name("uridecodebin")
assert isinstance(uridecodebin, Gst.Element)
# Set file URI
uridecodebin.set_property("uri", Gst.filename_to_uri(str(file_item.full_path)))
try:
# Set pipeline to PAUSED to get duration
pipeline.set_state(Gst.State.PAUSED)
pipeline.get_state(Gst.SECOND)
# Seek to 1/3 of duration
success, duration = pipeline.query_duration(Gst.Format.TIME)
if not success:
return
seek_pos = duration // 3
pipeline.seek_simple(
Gst.Format.TIME,
Gst.SeekFlags.FLUSH | Gst.SeekFlags.KEY_UNIT,
seek_pos,
)
# Start playing to capture frame
pipeline.set_state(Gst.State.PLAYING)
sample = sink.emit("pull-sample")
if not sample:
return
# Extract image data
buffer = sample.get_buffer()
if not buffer:
return
success, map_info = buffer.map(Gst.MapFlags.READ)
if not success:
return
try:
file_item.thumbnail = bytes(map_info.data)
file_item.has_thumbnail = True
finally:
buffer.unmap(map_info)
except Exception as err:
print("Failed:", file_item.full_path, err)
finally:
pipeline.set_state(Gst.State.NULL)