Refa:replace trio with asyncio (#11831)

### What problem does this PR solve?

change:
replace trio with asyncio

### Type of change
- [x] Refactoring

deepdoc/vision/t_ocr.py

@@ -14,6 +14,8 @@
 #  limitations under the License.
 #
 
+import asyncio
+import logging
 import os
 import sys
 sys.path.insert(
@@ -28,7 +30,6 @@ from deepdoc.vision.seeit import draw_box
 from deepdoc.vision import OCR, init_in_out
 import argparse
 import numpy as np
-import trio
 
 # os.environ['CUDA_VISIBLE_DEVICES'] = '0,2' #2 gpus, uncontinuous
 os.environ['CUDA_VISIBLE_DEVICES'] = '0' #1 gpu
@@ -39,7 +40,7 @@ def main(args):
     import torch.cuda
 
     cuda_devices = torch.cuda.device_count()
-    limiter = [trio.CapacityLimiter(1) for _ in range(cuda_devices)] if cuda_devices > 1 else None
+    limiter = [asyncio.Semaphore(1) for _ in range(cuda_devices)] if cuda_devices > 1 else None
     ocr = OCR()
     images, outputs = init_in_out(args)
 
@@ -62,22 +63,29 @@ def main(args):
     async def __ocr_thread(i, id, img, limiter = None):
         if limiter:
             async with limiter:
-                print("Task {} use device {}".format(i, id))
-                await trio.to_thread.run_sync(lambda: __ocr(i, id, img))
+                print(f"Task {i} use device {id}")
+                await asyncio.to_thread(__ocr, i, id, img)
         else:
-            __ocr(i, id, img)
+            await asyncio.to_thread(__ocr, i, id, img)
+
 
     async def __ocr_launcher():
-        if cuda_devices > 1:
-            async with trio.open_nursery() as nursery:
-                for i, img in enumerate(images):
-                    nursery.start_soon(__ocr_thread, i, i % cuda_devices, img, limiter[i % cuda_devices])
-                    await trio.sleep(0.1)
-        else:
-            for i, img in enumerate(images):
-                await __ocr_thread(i, 0, img)
+        tasks = []
+        for i, img in enumerate(images):
+            dev_id = i % cuda_devices if cuda_devices > 1 else 0
+            semaphore = limiter[dev_id] if limiter else None
+            tasks.append(asyncio.create_task(__ocr_thread(i, dev_id, img, semaphore)))
 
-    trio.run(__ocr_launcher)
+        try:
+            await asyncio.gather(*tasks, return_exceptions=False)
+        except Exception as e:
+            logging.error("OCR tasks failed: {}".format(e))
+            for t in tasks:
+                t.cancel()
+            await asyncio.gather(*tasks, return_exceptions=True)
+            raise
+
+    asyncio.run(__ocr_launcher())
 
     print("OCR tasks are all done")