From 2a05e5f30a2c2a07cb5fab612de9709d7f6b6ae3 Mon Sep 17 00:00:00 2001
From: Bruno Korbar <bkorbar@quansight.com>
Date: Fri, 18 Mar 2022 14:05:33 +0000
Subject: [PATCH 01/18] fix for FFMPEG 5.0

---
 torchvision/csrc/io/decoder/decoder.cpp       | 50 +++++++------------
 torchvision/csrc/io/decoder/stream.cpp        |  2 +-
 .../csrc/io/decoder/subtitle_stream.cpp       | 22 +++++---
 3 files changed, 32 insertions(+), 42 deletions(-)

diff --git a/torchvision/csrc/io/decoder/decoder.cpp b/torchvision/csrc/io/decoder/decoder.cpp
index 9ff2bd75bb5..e24f4592eb6 100644
--- a/torchvision/csrc/io/decoder/decoder.cpp
+++ b/torchvision/csrc/io/decoder/decoder.cpp
@@ -18,25 +18,6 @@ constexpr size_t kIoBufferSize = 96 * 1024;
 constexpr size_t kIoPaddingSize = AV_INPUT_BUFFER_PADDING_SIZE;
 constexpr size_t kLogBufferSize = 1024;
 
-int ffmpeg_lock(void** mutex, enum AVLockOp op) {
-  std::mutex** handle = (std::mutex**)mutex;
-  switch (op) {
-    case AV_LOCK_CREATE:
-      *handle = new std::mutex();
-      break;
-    case AV_LOCK_OBTAIN:
-      (*handle)->lock();
-      break;
-    case AV_LOCK_RELEASE:
-      (*handle)->unlock();
-      break;
-    case AV_LOCK_DESTROY:
-      delete *handle;
-      break;
-  }
-  return 0;
-}
-
 bool mapFfmpegType(AVMediaType media, MediaType* type) {
   switch (media) {
     case AVMEDIA_TYPE_AUDIO:
@@ -202,8 +183,6 @@ void Decoder::initOnce() {
     avcodec_register_all();
 #endif
     avformat_network_init();
-    // register ffmpeg lock manager
-    av_lockmgr_register(&ffmpeg_lock);
     av_log_set_callback(Decoder::logFunction);
     av_log_set_level(AV_LOG_ERROR);
     VLOG(1) << "Registered ffmpeg libs";
@@ -277,7 +256,7 @@ bool Decoder::init(
           break;
       }
 
-      fmt = av_find_input_format(fmtName);
+      fmt = (AVInputFormat*)av_find_input_format(fmtName);
     }
 
     const size_t avioCtxBufferSize = kIoBufferSize;
@@ -505,10 +484,14 @@ int Decoder::getFrame(size_t workingTimeInMs) {
   // once decode() method gets called and grab some bytes
   // run this method again
   // init package
-  AVPacket avPacket;
-  av_init_packet(&avPacket);
-  avPacket.data = nullptr;
-  avPacket.size = 0;
+  // update 03/22: moving memory management to ffmpeg
+  AVPacket* avPacket;
+  avPacket = av_packet_alloc();
+  if (avPacket == NULL) {
+    LOG(ERROR) << "decoder as not able to allocate the packet.";
+  }
+  avPacket->data = nullptr;
+  avPacket->size = 0;
 
   auto end = std::chrono::steady_clock::now() +
       std::chrono::milliseconds(workingTimeInMs);
@@ -521,7 +504,7 @@ int Decoder::getFrame(size_t workingTimeInMs) {
   size_t decodingErrors = 0;
   bool decodedFrame = false;
   while (!interrupted_ && inRange_.any() && !decodedFrame && watcher()) {
-    result = av_read_frame(inputCtx_, &avPacket);
+    result = av_read_frame(inputCtx_, avPacket);
     if (result == AVERROR(EAGAIN)) {
       VLOG(4) << "Decoder is busy...";
       std::this_thread::yield();
@@ -538,10 +521,11 @@ int Decoder::getFrame(size_t workingTimeInMs) {
       break;
     }
 
-    // get stream
-    auto stream = findByIndex(avPacket.stream_index);
+    // get stream; if stream cannot be found reset the packet to
+    // default settings
+    auto stream = findByIndex(avPacket->stream_index);
     if (stream == nullptr || !inRange_.test(stream->getIndex())) {
-      av_packet_unref(&avPacket);
+      av_packet_unref(avPacket);
       continue;
     }
 
@@ -553,7 +537,7 @@ int Decoder::getFrame(size_t workingTimeInMs) {
       bool hasMsg = false;
       // packet either got consumed completely or not at all
       if ((result = processPacket(
-               stream, &avPacket, &gotFrame, &hasMsg, params_.fastSeek)) < 0) {
+               stream, avPacket, &gotFrame, &hasMsg, params_.fastSeek)) < 0) {
         LOG(ERROR) << "processPacket failed with code: " << result;
         break;
       }
@@ -585,10 +569,10 @@ int Decoder::getFrame(size_t workingTimeInMs) {
 
     result = 0;
 
-    av_packet_unref(&avPacket);
+    av_packet_unref(avPacket);
   }
 
-  av_packet_unref(&avPacket);
+  av_packet_unref(avPacket);
 
   VLOG(2) << "Interrupted loop"
           << ", interrupted_ " << interrupted_ << ", inRange_.any() "
diff --git a/torchvision/csrc/io/decoder/stream.cpp b/torchvision/csrc/io/decoder/stream.cpp
index 3fd49efbfc7..0d625ef211c 100644
--- a/torchvision/csrc/io/decoder/stream.cpp
+++ b/torchvision/csrc/io/decoder/stream.cpp
@@ -28,7 +28,7 @@ Stream::~Stream() {
 
 // look up the proper CODEC querying the function
 AVCodec* Stream::findCodec(AVCodecParameters* params) {
-  return avcodec_find_decoder(params->codec_id);
+  return (AVCodec*)avcodec_find_decoder(params->codec_id);
 }
 
 // Allocate memory for the AVCodecContext, which will hold the context for
diff --git a/torchvision/csrc/io/decoder/subtitle_stream.cpp b/torchvision/csrc/io/decoder/subtitle_stream.cpp
index 0d3fc9f12c1..e1d29bc7bb9 100644
--- a/torchvision/csrc/io/decoder/subtitle_stream.cpp
+++ b/torchvision/csrc/io/decoder/subtitle_stream.cpp
@@ -44,20 +44,26 @@ int SubtitleStream::analyzePacket(const AVPacket* packet, bool* gotFrame) {
   // clean-up
   releaseSubtitle();
   // check flush packet
-  AVPacket avPacket;
-  av_init_packet(&avPacket);
-  avPacket.data = nullptr;
-  avPacket.size = 0;
-  auto pkt = packet ? *packet : avPacket;
+  AVPacket* avPacket;
+  avPacket = av_packet_alloc();
+  if (avPacket == NULL) {
+    LOG(ERROR) << "decoder as not able to allocate the packet.";
+  }
+  avPacket->data = nullptr;
+  avPacket->size = 0;
+
+  auto pkt = packet ? packet : avPacket;
   int gotFramePtr = 0;
-  int result = avcodec_decode_subtitle2(codecCtx_, &sub_, &gotFramePtr, &pkt);
+  // is these a better way than cast from const?
+  int result =
+      avcodec_decode_subtitle2(codecCtx_, &sub_, &gotFramePtr, (AVPacket*)pkt);
 
   if (result < 0) {
     LOG(ERROR) << "avcodec_decode_subtitle2 failed, err: "
                << Util::generateErrorDesc(result);
     return result;
   } else if (result == 0) {
-    result = pkt.size; // discard the rest of the package
+    result = pkt->size; // discard the rest of the package
   }
 
   sub_.release = gotFramePtr;
@@ -66,7 +72,7 @@ int SubtitleStream::analyzePacket(const AVPacket* packet, bool* gotFrame) {
   // set proper pts in us
   if (gotFramePtr) {
     sub_.pts = av_rescale_q(
-        pkt.pts, inputCtx_->streams[format_.stream]->time_base, timeBaseQ);
+        pkt->pts, inputCtx_->streams[format_.stream]->time_base, timeBaseQ);
   }
 
   return result;

From 3a927c6e7b09e8fde545d940fb80e6faaf250032 Mon Sep 17 00:00:00 2001
From: Joao Gomes <jdsgomes@fb.com>
Date: Tue, 22 Mar 2022 14:12:29 +0000
Subject: [PATCH 02/18] Attempt to fix memory leak

---
 torchvision/csrc/io/decoder/decoder.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/torchvision/csrc/io/decoder/decoder.cpp b/torchvision/csrc/io/decoder/decoder.cpp
index e24f4592eb6..f167a264e13 100644
--- a/torchvision/csrc/io/decoder/decoder.cpp
+++ b/torchvision/csrc/io/decoder/decoder.cpp
@@ -497,6 +497,7 @@ int Decoder::getFrame(size_t workingTimeInMs) {
       std::chrono::milliseconds(workingTimeInMs);
   // return true if elapsed time less than timeout
   auto watcher = [end]() -> bool {
+    av_packet_free(&avPacket);
     return std::chrono::steady_clock::now() <= end;
   };
 
@@ -585,6 +586,7 @@ int Decoder::getFrame(size_t workingTimeInMs) {
   // 3. unrecoverable error or ENODATA (end of stream)
   // 4. decoded frames pts are out of the specified range
   // 5. success decoded frame
+  av_packet_free(&avPacket);
   if (interrupted_) {
     return EINTR;
   }

From 7984483358138dac2bf575ea913ba3a740db6452 Mon Sep 17 00:00:00 2001
From: Joao Gomes <jdsgomes@fb.com>
Date: Tue, 22 Mar 2022 14:19:22 +0000
Subject: [PATCH 03/18] early stop when mem alloc fails

---
 torchvision/csrc/io/decoder/decoder.cpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/torchvision/csrc/io/decoder/decoder.cpp b/torchvision/csrc/io/decoder/decoder.cpp
index f167a264e13..ed35d85370e 100644
--- a/torchvision/csrc/io/decoder/decoder.cpp
+++ b/torchvision/csrc/io/decoder/decoder.cpp
@@ -4,6 +4,7 @@
 #include <future>
 #include <iostream>
 #include <mutex>
+#include <cerrno>
 #include "audio_stream.h"
 #include "cc_stream.h"
 #include "subtitle_stream.h"
@@ -487,8 +488,10 @@ int Decoder::getFrame(size_t workingTimeInMs) {
   // update 03/22: moving memory management to ffmpeg
   AVPacket* avPacket;
   avPacket = av_packet_alloc();
-  if (avPacket == NULL) {
+  if (avPacket == nullptr) {
     LOG(ERROR) << "decoder as not able to allocate the packet.";
+    av_packet_free(&avPacket);
+    return ENOMEM;
   }
   avPacket->data = nullptr;
   avPacket->size = 0;

From f9c898723a41f96ab593adfc8275e3ea34131410 Mon Sep 17 00:00:00 2001
From: Joao Gomes <jdsgomes@fb.com>
Date: Tue, 22 Mar 2022 14:31:00 +0000
Subject: [PATCH 04/18] fix c lint error

---
 torchvision/csrc/io/decoder/decoder.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/torchvision/csrc/io/decoder/decoder.cpp b/torchvision/csrc/io/decoder/decoder.cpp
index ed35d85370e..3779f2fadcf 100644
--- a/torchvision/csrc/io/decoder/decoder.cpp
+++ b/torchvision/csrc/io/decoder/decoder.cpp
@@ -1,10 +1,10 @@
 #include "decoder.h"
 #include <c10/util/Logging.h>
 #include <libavutil/avutil.h>
+#include <cerrno>
 #include <future>
 #include <iostream>
 #include <mutex>
-#include <cerrno>
 #include "audio_stream.h"
 #include "cc_stream.h"
 #include "subtitle_stream.h"

From 4c6c8fceb508a03b6f5a4d0856ff24dc77a8f305 Mon Sep 17 00:00:00 2001
From: Joao Gomes <jdsgomes@fb.com>
Date: Tue, 22 Mar 2022 14:44:33 +0000
Subject: [PATCH 05/18] fix bug

---
 torchvision/csrc/io/decoder/decoder.cpp | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/torchvision/csrc/io/decoder/decoder.cpp b/torchvision/csrc/io/decoder/decoder.cpp
index 3779f2fadcf..c69476f5e6f 100644
--- a/torchvision/csrc/io/decoder/decoder.cpp
+++ b/torchvision/csrc/io/decoder/decoder.cpp
@@ -490,7 +490,7 @@ int Decoder::getFrame(size_t workingTimeInMs) {
   avPacket = av_packet_alloc();
   if (avPacket == nullptr) {
     LOG(ERROR) << "decoder as not able to allocate the packet.";
-    av_packet_free(&avPacket);
+    av_packet_free(avPacket);
     return ENOMEM;
   }
   avPacket->data = nullptr;
@@ -500,7 +500,7 @@ int Decoder::getFrame(size_t workingTimeInMs) {
       std::chrono::milliseconds(workingTimeInMs);
   // return true if elapsed time less than timeout
   auto watcher = [end]() -> bool {
-    av_packet_free(&avPacket);
+    av_packet_free(avPacket);
     return std::chrono::steady_clock::now() <= end;
   };
 
@@ -589,7 +589,7 @@ int Decoder::getFrame(size_t workingTimeInMs) {
   // 3. unrecoverable error or ENODATA (end of stream)
   // 4. decoded frames pts are out of the specified range
   // 5. success decoded frame
-  av_packet_free(&avPacket);
+  av_packet_free(avPacket);
   if (interrupted_) {
     return EINTR;
   }

From 08232e4246a1b1c1cb4b2bbcbddb015c5fbc573b Mon Sep 17 00:00:00 2001
From: Joao Gomes <jdsgomes@fb.com>
Date: Tue, 22 Mar 2022 15:01:40 +0000
Subject: [PATCH 06/18] revert changes

---
 torchvision/csrc/io/decoder/decoder.cpp | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/torchvision/csrc/io/decoder/decoder.cpp b/torchvision/csrc/io/decoder/decoder.cpp
index c69476f5e6f..3779f2fadcf 100644
--- a/torchvision/csrc/io/decoder/decoder.cpp
+++ b/torchvision/csrc/io/decoder/decoder.cpp
@@ -490,7 +490,7 @@ int Decoder::getFrame(size_t workingTimeInMs) {
   avPacket = av_packet_alloc();
   if (avPacket == nullptr) {
     LOG(ERROR) << "decoder as not able to allocate the packet.";
-    av_packet_free(avPacket);
+    av_packet_free(&avPacket);
     return ENOMEM;
   }
   avPacket->data = nullptr;
@@ -500,7 +500,7 @@ int Decoder::getFrame(size_t workingTimeInMs) {
       std::chrono::milliseconds(workingTimeInMs);
   // return true if elapsed time less than timeout
   auto watcher = [end]() -> bool {
-    av_packet_free(avPacket);
+    av_packet_free(&avPacket);
     return std::chrono::steady_clock::now() <= end;
   };
 
@@ -589,7 +589,7 @@ int Decoder::getFrame(size_t workingTimeInMs) {
   // 3. unrecoverable error or ENODATA (end of stream)
   // 4. decoded frames pts are out of the specified range
   // 5. success decoded frame
-  av_packet_free(avPacket);
+  av_packet_free(&avPacket);
   if (interrupted_) {
     return EINTR;
   }

From 2f79d6c5ec5f09a803ac7f4e4e2a3608cff64f77 Mon Sep 17 00:00:00 2001
From: Joao Gomes <jdsgomes@fb.com>
Date: Tue, 22 Mar 2022 15:38:38 +0000
Subject: [PATCH 07/18] remove incorrect av_packet_free

---
 torchvision/csrc/io/decoder/decoder.cpp | 1 -
 1 file changed, 1 deletion(-)

diff --git a/torchvision/csrc/io/decoder/decoder.cpp b/torchvision/csrc/io/decoder/decoder.cpp
index 3779f2fadcf..76ece7839a0 100644
--- a/torchvision/csrc/io/decoder/decoder.cpp
+++ b/torchvision/csrc/io/decoder/decoder.cpp
@@ -490,7 +490,6 @@ int Decoder::getFrame(size_t workingTimeInMs) {
   avPacket = av_packet_alloc();
   if (avPacket == nullptr) {
     LOG(ERROR) << "decoder as not able to allocate the packet.";
-    av_packet_free(&avPacket);
     return ENOMEM;
   }
   avPacket->data = nullptr;

From d124ee1b2874941cf1d46fa7f8fdd0d2ab4e6354 Mon Sep 17 00:00:00 2001
From: Bruno Korbar <bkorbar@quansight.com>
Date: Wed, 23 Mar 2022 11:58:57 +0000
Subject: [PATCH 08/18] add `av_packet_free` to subtitle stream

---
 torchvision/csrc/io/decoder/subtitle_stream.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/torchvision/csrc/io/decoder/subtitle_stream.cpp b/torchvision/csrc/io/decoder/subtitle_stream.cpp
index e1d29bc7bb9..ac97628bdff 100644
--- a/torchvision/csrc/io/decoder/subtitle_stream.cpp
+++ b/torchvision/csrc/io/decoder/subtitle_stream.cpp
@@ -61,6 +61,8 @@ int SubtitleStream::analyzePacket(const AVPacket* packet, bool* gotFrame) {
   if (result < 0) {
     LOG(ERROR) << "avcodec_decode_subtitle2 failed, err: "
                << Util::generateErrorDesc(result);
+    // free packet
+    av_packet_free(&avPacket);
     return result;
   } else if (result == 0) {
     result = pkt->size; // discard the rest of the package
@@ -75,6 +77,7 @@ int SubtitleStream::analyzePacket(const AVPacket* packet, bool* gotFrame) {
         pkt->pts, inputCtx_->streams[format_.stream]->time_base, timeBaseQ);
   }
 
+  av_packet_free(&avPacket);
   return result;
 }
 

From 2f7c02a1e0dd3b0f9f358fef7156141c28b733d9 Mon Sep 17 00:00:00 2001
From: Bruno Korbar <bkorbar@quansight.com>
Date: Thu, 24 Mar 2022 10:10:24 +0000
Subject: [PATCH 09/18] Addressing subtitle stream comments

---
 torchvision/csrc/io/decoder/subtitle_stream.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/torchvision/csrc/io/decoder/subtitle_stream.cpp b/torchvision/csrc/io/decoder/subtitle_stream.cpp
index ac97628bdff..5d6b4fa8421 100644
--- a/torchvision/csrc/io/decoder/subtitle_stream.cpp
+++ b/torchvision/csrc/io/decoder/subtitle_stream.cpp
@@ -46,8 +46,10 @@ int SubtitleStream::analyzePacket(const AVPacket* packet, bool* gotFrame) {
   // check flush packet
   AVPacket* avPacket;
   avPacket = av_packet_alloc();
-  if (avPacket == NULL) {
-    LOG(ERROR) << "decoder as not able to allocate the packet.";
+  if (avPacket == nullptr) {
+    LOG(ERROR)
+        << "decoder as not able to allocate the subtitle-specific packet.";
+    return ENOMEM;
   }
   avPacket->data = nullptr;
   avPacket->size = 0;

From 926a11e7d8fab01597ee31560e7206ebc6d30892 Mon Sep 17 00:00:00 2001
From: Bruno Korbar <bkorbar@quansight.com>
Date: Thu, 24 Mar 2022 10:16:54 +0000
Subject: [PATCH 10/18] addressing decoder changes

---
 torchvision/csrc/io/decoder/decoder.cpp | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/torchvision/csrc/io/decoder/decoder.cpp b/torchvision/csrc/io/decoder/decoder.cpp
index 76ece7839a0..e96da5a5bee 100644
--- a/torchvision/csrc/io/decoder/decoder.cpp
+++ b/torchvision/csrc/io/decoder/decoder.cpp
@@ -575,8 +575,7 @@ int Decoder::getFrame(size_t workingTimeInMs) {
     av_packet_unref(avPacket);
   }
 
-  av_packet_unref(avPacket);
-
+  av_packet_free(&avPacket);
   VLOG(2) << "Interrupted loop"
           << ", interrupted_ " << interrupted_ << ", inRange_.any() "
           << inRange_.any() << ", decodedFrame " << decodedFrame << ", result "
@@ -588,7 +587,6 @@ int Decoder::getFrame(size_t workingTimeInMs) {
   // 3. unrecoverable error or ENODATA (end of stream)
   // 4. decoded frames pts are out of the specified range
   // 5. success decoded frame
-  av_packet_free(&avPacket);
   if (interrupted_) {
     return EINTR;
   }

From 2602ef4dfff353356b76f8d7cf00637c6ae52871 Mon Sep 17 00:00:00 2001
From: Bruno Korbar <bkorbar@quansight.com>
Date: Thu, 24 Mar 2022 10:19:12 +0000
Subject: [PATCH 11/18] nit

---
 .../csrc/io/decoder/subtitle_stream.cpp       | 24 +++++++++++--------
 1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/torchvision/csrc/io/decoder/subtitle_stream.cpp b/torchvision/csrc/io/decoder/subtitle_stream.cpp
index 5d6b4fa8421..1e3e9f419ba 100644
--- a/torchvision/csrc/io/decoder/subtitle_stream.cpp
+++ b/torchvision/csrc/io/decoder/subtitle_stream.cpp
@@ -43,18 +43,22 @@ int SubtitleStream::initFormat() {
 int SubtitleStream::analyzePacket(const AVPacket* packet, bool* gotFrame) {
   // clean-up
   releaseSubtitle();
-  // check flush packet
-  AVPacket* avPacket;
-  avPacket = av_packet_alloc();
-  if (avPacket == nullptr) {
-    LOG(ERROR)
-        << "decoder as not able to allocate the subtitle-specific packet.";
-    return ENOMEM;
+
+  auto pkt = packet;
+  if (pkt == nullptr) {
+    // check flush packet
+    AVPacket* avPacket;
+    avPacket = av_packet_alloc();
+    if (avPacket == nullptr) {
+      LOG(ERROR)
+          << "decoder as not able to allocate the subtitle-specific packet.";
+      return ENOMEM;
+    }
+    avPacket->data = nullptr;
+    avPacket->size = 0;
+    pkt = avPacket;
   }
-  avPacket->data = nullptr;
-  avPacket->size = 0;
 
-  auto pkt = packet ? packet : avPacket;
   int gotFramePtr = 0;
   // is these a better way than cast from const?
   int result =

From b978ba12586e7aae5d8f17dbdf30e35b5f37a322 Mon Sep 17 00:00:00 2001
From: Bruno Korbar <bkorbar@quansight.com>
Date: Thu, 24 Mar 2022 10:59:15 +0000
Subject: [PATCH 12/18] addressing datumbox concernsz

---
 .../csrc/io/decoder/subtitle_stream.cpp       | 27 +++++++++----------
 1 file changed, 12 insertions(+), 15 deletions(-)

diff --git a/torchvision/csrc/io/decoder/subtitle_stream.cpp b/torchvision/csrc/io/decoder/subtitle_stream.cpp
index 1e3e9f419ba..c4fbf00790a 100644
--- a/torchvision/csrc/io/decoder/subtitle_stream.cpp
+++ b/torchvision/csrc/io/decoder/subtitle_stream.cpp
@@ -44,20 +44,18 @@ int SubtitleStream::analyzePacket(const AVPacket* packet, bool* gotFrame) {
   // clean-up
   releaseSubtitle();
 
-  auto pkt = packet;
-  if (pkt == nullptr) {
-    // check flush packet
-    AVPacket* avPacket;
-    avPacket = av_packet_alloc();
-    if (avPacket == nullptr) {
-      LOG(ERROR)
-          << "decoder as not able to allocate the subtitle-specific packet.";
-      return ENOMEM;
-    }
-    avPacket->data = nullptr;
-    avPacket->size = 0;
-    pkt = avPacket;
+  // FIXME: should this even be created?
+  AVPacket* avPacket;
+  avPacket = av_packet_alloc();
+  if (avPacket == nullptr) {
+    LOG(ERROR)
+        << "decoder as not able to allocate the subtitle-specific packet.";
+    return ENOMEM;
   }
+  avPacket->data = nullptr;
+  avPacket->size = 0;
+  // check flush packet
+  auto pkt = packet ? packet : avPacket;
 
   int gotFramePtr = 0;
   // is these a better way than cast from const?
@@ -67,7 +65,7 @@ int SubtitleStream::analyzePacket(const AVPacket* packet, bool* gotFrame) {
   if (result < 0) {
     LOG(ERROR) << "avcodec_decode_subtitle2 failed, err: "
                << Util::generateErrorDesc(result);
-    // free packet
+    // free the packet we've created
     av_packet_free(&avPacket);
     return result;
   } else if (result == 0) {
@@ -83,7 +81,6 @@ int SubtitleStream::analyzePacket(const AVPacket* packet, bool* gotFrame) {
         pkt->pts, inputCtx_->streams[format_.stream]->time_base, timeBaseQ);
   }
 
-  av_packet_free(&avPacket);
   return result;
 }
 

From 0f02ed93a49875b80f36399cb04aeae74040746e Mon Sep 17 00:00:00 2001
From: Bruno Korbar <bkorbar@quansight.com>
Date: Thu, 24 Mar 2022 11:21:44 +0000
Subject: [PATCH 13/18] averror push

---
 torchvision/csrc/io/decoder/decoder.cpp         | 2 +-
 torchvision/csrc/io/decoder/subtitle_stream.cpp | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/torchvision/csrc/io/decoder/decoder.cpp b/torchvision/csrc/io/decoder/decoder.cpp
index e96da5a5bee..7c53d302b3c 100644
--- a/torchvision/csrc/io/decoder/decoder.cpp
+++ b/torchvision/csrc/io/decoder/decoder.cpp
@@ -490,7 +490,7 @@ int Decoder::getFrame(size_t workingTimeInMs) {
   avPacket = av_packet_alloc();
   if (avPacket == nullptr) {
     LOG(ERROR) << "decoder as not able to allocate the packet.";
-    return ENOMEM;
+    return AVERROR_BUFFER_TOO_SMALL;
   }
   avPacket->data = nullptr;
   avPacket->size = 0;
diff --git a/torchvision/csrc/io/decoder/subtitle_stream.cpp b/torchvision/csrc/io/decoder/subtitle_stream.cpp
index c4fbf00790a..ac0c777070b 100644
--- a/torchvision/csrc/io/decoder/subtitle_stream.cpp
+++ b/torchvision/csrc/io/decoder/subtitle_stream.cpp
@@ -50,7 +50,8 @@ int SubtitleStream::analyzePacket(const AVPacket* packet, bool* gotFrame) {
   if (avPacket == nullptr) {
     LOG(ERROR)
         << "decoder as not able to allocate the subtitle-specific packet.";
-    return ENOMEM;
+    // alternative to ENOMEM
+    return AVERROR_BUFFER_TOO_SMALL;
   }
   avPacket->data = nullptr;
   avPacket->size = 0;

From 50d234f8a13ffc8c8416fbfbc06116869f6402ee Mon Sep 17 00:00:00 2001
From: Bruno Korbar <bkorbar@quansight.com>
Date: Thu, 24 Mar 2022 13:03:45 +0000
Subject: [PATCH 14/18] addressing comments

---
 torchvision/csrc/io/decoder/decoder.cpp         | 3 +--
 torchvision/csrc/io/decoder/subtitle_stream.cpp | 1 +
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/torchvision/csrc/io/decoder/decoder.cpp b/torchvision/csrc/io/decoder/decoder.cpp
index 7c53d302b3c..c34049b909f 100644
--- a/torchvision/csrc/io/decoder/decoder.cpp
+++ b/torchvision/csrc/io/decoder/decoder.cpp
@@ -490,7 +490,7 @@ int Decoder::getFrame(size_t workingTimeInMs) {
   avPacket = av_packet_alloc();
   if (avPacket == nullptr) {
     LOG(ERROR) << "decoder as not able to allocate the packet.";
-    return AVERROR_BUFFER_TOO_SMALL;
+    return AVERROR(ENOMEM);
   }
   avPacket->data = nullptr;
   avPacket->size = 0;
@@ -499,7 +499,6 @@ int Decoder::getFrame(size_t workingTimeInMs) {
       std::chrono::milliseconds(workingTimeInMs);
   // return true if elapsed time less than timeout
   auto watcher = [end]() -> bool {
-    av_packet_free(&avPacket);
     return std::chrono::steady_clock::now() <= end;
   };
 
diff --git a/torchvision/csrc/io/decoder/subtitle_stream.cpp b/torchvision/csrc/io/decoder/subtitle_stream.cpp
index ac0c777070b..27c61d4dbd9 100644
--- a/torchvision/csrc/io/decoder/subtitle_stream.cpp
+++ b/torchvision/csrc/io/decoder/subtitle_stream.cpp
@@ -82,6 +82,7 @@ int SubtitleStream::analyzePacket(const AVPacket* packet, bool* gotFrame) {
         pkt->pts, inputCtx_->streams[format_.stream]->time_base, timeBaseQ);
   }
 
+  av_packet_free(&avPacket);
   return result;
 }
 

From f0212c04fbe89c7db4505cf527274b343048dd12 Mon Sep 17 00:00:00 2001
From: Joao Gomes <joaopsgomes@gmail.com>
Date: Fri, 25 Mar 2022 12:52:15 +0000
Subject: [PATCH 15/18] Apply suggestions from code review

---
 torchvision/csrc/io/decoder/decoder.cpp | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/torchvision/csrc/io/decoder/decoder.cpp b/torchvision/csrc/io/decoder/decoder.cpp
index c34049b909f..ce3a44274c7 100644
--- a/torchvision/csrc/io/decoder/decoder.cpp
+++ b/torchvision/csrc/io/decoder/decoder.cpp
@@ -1,7 +1,6 @@
 #include "decoder.h"
 #include <c10/util/Logging.h>
 #include <libavutil/avutil.h>
-#include <cerrno>
 #include <future>
 #include <iostream>
 #include <mutex>
@@ -490,7 +489,7 @@ int Decoder::getFrame(size_t workingTimeInMs) {
   avPacket = av_packet_alloc();
   if (avPacket == nullptr) {
     LOG(ERROR) << "decoder as not able to allocate the packet.";
-    return AVERROR(ENOMEM);
+    return AVERROR_BUFFER_TOO_SMALL;
   }
   avPacket->data = nullptr;
   avPacket->size = 0;

From 1811fa1bf281a2ee41f0c5bfa55523a7862866b4 Mon Sep 17 00:00:00 2001
From: Joao Gomes <jdsgomes@fb.com>
Date: Fri, 25 Mar 2022 13:20:33 +0000
Subject: [PATCH 16/18] add new error code to documentation

---
 torchvision/csrc/io/decoder/decoder.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/torchvision/csrc/io/decoder/decoder.cpp b/torchvision/csrc/io/decoder/decoder.cpp
index ce3a44274c7..4a91e5c7742 100644
--- a/torchvision/csrc/io/decoder/decoder.cpp
+++ b/torchvision/csrc/io/decoder/decoder.cpp
@@ -475,7 +475,8 @@ void Decoder::cleanUp() {
 // function does actual work, derived class calls it in working thread
 // periodically. On success method returns 0, ENODATA on EOF, ETIMEDOUT if
 // no frames got decoded in the specified timeout time, and error on
-// unrecoverable error.
+// unrecoverable error or AVERROR_BUFFER_TOO_SMALL when unable to allocate 
+// packet.
 int Decoder::getFrame(size_t workingTimeInMs) {
   if (inRange_.none()) {
     return ENODATA;

From 93e0863cdee6e2b590d7599c1c0f45a288b061b6 Mon Sep 17 00:00:00 2001
From: Joao Gomes <jdsgomes@fb.com>
Date: Fri, 25 Mar 2022 14:28:33 +0000
Subject: [PATCH 17/18] re-introducing timeout

---
 torchvision/csrc/io/decoder/decoder.cpp | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/torchvision/csrc/io/decoder/decoder.cpp b/torchvision/csrc/io/decoder/decoder.cpp
index 4a91e5c7742..c9105e4709d 100644
--- a/torchvision/csrc/io/decoder/decoder.cpp
+++ b/torchvision/csrc/io/decoder/decoder.cpp
@@ -474,9 +474,8 @@ void Decoder::cleanUp() {
 
 // function does actual work, derived class calls it in working thread
 // periodically. On success method returns 0, ENODATA on EOF, ETIMEDOUT if
-// no frames got decoded in the specified timeout time, and error on
-// unrecoverable error or AVERROR_BUFFER_TOO_SMALL when unable to allocate 
-// packet.
+// no frames got decoded in the specified timeout time, AVERROR_BUFFER_TOO_SMALL
+// when unable to allocate packet and error on unrecoverable error
 int Decoder::getFrame(size_t workingTimeInMs) {
   if (inRange_.none()) {
     return ENODATA;
@@ -505,7 +504,10 @@ int Decoder::getFrame(size_t workingTimeInMs) {
   int result = 0;
   size_t decodingErrors = 0;
   bool decodedFrame = false;
-  while (!interrupted_ && inRange_.any() && !decodedFrame && watcher()) {
+  while (!interrupted_ && inRange_.any() && !decodedFrame) {
+    if watcher() == false:
+      result = ETIMEDOUT
+      break;
     result = av_read_frame(inputCtx_, avPacket);
     if (result == AVERROR(EAGAIN)) {
       VLOG(4) << "Decoder is busy...";
@@ -582,8 +584,7 @@ int Decoder::getFrame(size_t workingTimeInMs) {
 
   // loop can be terminated, either by:
   // 1. explcitly iterrupted
-  // 2. terminated by workable timeout
-  // 3. unrecoverable error or ENODATA (end of stream)
+  // 3. unrecoverable error or ENODATA (end of stream) or ETIMEDOUT (timeout)
   // 4. decoded frames pts are out of the specified range
   // 5. success decoded frame
   if (interrupted_) {

From 3487c680fc86358fc2d4f9109d2c3fa0df6e4e54 Mon Sep 17 00:00:00 2001
From: Joao Gomes <jdsgomes@fb.com>
Date: Fri, 25 Mar 2022 14:32:06 +0000
Subject: [PATCH 18/18] fix c++ syntax

---
 torchvision/csrc/io/decoder/decoder.cpp | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/torchvision/csrc/io/decoder/decoder.cpp b/torchvision/csrc/io/decoder/decoder.cpp
index c9105e4709d..845a0cc80ad 100644
--- a/torchvision/csrc/io/decoder/decoder.cpp
+++ b/torchvision/csrc/io/decoder/decoder.cpp
@@ -505,9 +505,10 @@ int Decoder::getFrame(size_t workingTimeInMs) {
   size_t decodingErrors = 0;
   bool decodedFrame = false;
   while (!interrupted_ && inRange_.any() && !decodedFrame) {
-    if watcher() == false:
-      result = ETIMEDOUT
+    if (watcher() == false) {
+      result = ETIMEDOUT;
       break;
+    }
     result = av_read_frame(inputCtx_, avPacket);
     if (result == AVERROR(EAGAIN)) {
       VLOG(4) << "Decoder is busy...";