media download speed ​​up:skip sleep if download not start or media type not match

telegram_export/downloader.py

@@ -226,7 +226,7 @@ async def _download_media(self, media_id, context_id, sender_id, date,
         media_type = media_row[3].split('.')
         media_type, media_subtype = media_type[0], media_type[-1]
         if media_type not in ('photo', 'document'):
-            return  # Only photos or documents are actually downloadable
+            return False  # Only photos or documents are actually downloadable
 
         formatter = defaultdict(
             str,
@@ -260,7 +260,7 @@ async def _download_media(self, media_id, context_id, sender_id, date,
         filename += '.{}{}'.format(media_id, ext)
         if os.path.isfile(filename):
             __log__.debug('Skipping already-existing file %s', filename)
-            return
+            return False
 
         __log__.debug('Downloading to %s', filename)
         os.makedirs(os.path.dirname(filename), exist_ok=True)
@@ -301,16 +301,18 @@ def progress(saved, total):
             progress_callback=progress
         )
         self._incomplete_download = None
+        return True
 
     async def _media_consumer(self, queue, bar):
         while self._running:
             start = time.time()
             media_id, context_id, sender_id, date = await queue.get()
-            await self._download_media(media_id, context_id, sender_id,
+            need_sleep = await self._download_media(media_id, context_id, sender_id,
                                        datetime.datetime.utcfromtimestamp(date),
                                        bar)
             queue.task_done()
-            await asyncio.sleep(max(MEDIA_DELAY - (time.time() - start), 0),
+            if need_sleep:
+                await asyncio.sleep(max(MEDIA_DELAY - (time.time() - start), 0),
                                 loop=self.loop)
 
     async def _user_consumer(self, queue, bar):