From a79580dc9a1d422894374ead6823f9bc283b5981 Mon Sep 17 00:00:00 2001
From: Anand Tamariya <Anand Tamariya>
Date: Thu, 20 Dec 2018 14:47:07 +0530
Subject: [PATCH 1/3] Allow format to be specified by -f flag

---
 youtube_dl/downloader/external.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/youtube_dl/downloader/external.py b/youtube_dl/downloader/external.py
index 958d00aac..1ba839716 100644
--- a/youtube_dl/downloader/external.py
+++ b/youtube_dl/downloader/external.py
@@ -294,7 +294,7 @@ class FFmpegFD(ExternalFD):
             if live:
                 args += ['-rtmp_live', 'live']
 
-        args += ['-i', url, '-c', 'copy']
+        args += ['-i', url]
 
         if self.params.get('test', False):
             args += ['-fs', compat_str(self._TEST_FILE_SIZE)]

From f0cbbcf089f0f1119c44240f440c023f5bc4fee1 Mon Sep 17 00:00:00 2001
From: Anand Tamariya <Anand Tamariya>
Date: Mon, 24 Dec 2018 16:37:38 +0530
Subject: [PATCH 2/3] For MP4 format and stdout, use -movflags option.

---
 youtube_dl/downloader/external.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/youtube_dl/downloader/external.py b/youtube_dl/downloader/external.py
index 1ba839716..b6601d7ba 100644
--- a/youtube_dl/downloader/external.py
+++ b/youtube_dl/downloader/external.py
@@ -300,10 +300,12 @@ class FFmpegFD(ExternalFD):
             args += ['-fs', compat_str(self._TEST_FILE_SIZE)]
 
         if protocol in ('m3u8', 'm3u8_native'):
-            if self.params.get('hls_use_mpegts', False) or tmpfilename == '-':
+            if self.params.get('hls_use_mpegts', False):
                 args += ['-f', 'mpegts']
             else:
                 args += ['-f', 'mp4']
+                if tmpfilename == '-':
+                    args += ["-movflags", "frag_keyframe+empty_moov"]
                 if (ffpp.basename == 'ffmpeg' and is_outdated_version(ffpp._versions['ffmpeg'], '3.2', False)) and (not info_dict.get('acodec') or info_dict['acodec'].split('.')[0] in ('aac', 'mp4a')):
                     args += ['-bsf:a', 'aac_adtstoasc']
         elif protocol == 'rtmp':

From 7e9f0baefaec0a8050fa4d12b3977f9052643638 Mon Sep 17 00:00:00 2001
From: Anand Tamariya <Anand Tamariya>
Date: Thu, 27 Dec 2018 20:08:02 +0530
Subject: [PATCH 3/3] Use optimized ffmpeg params for pipe operation

---
 youtube_dl/downloader/external.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/youtube_dl/downloader/external.py b/youtube_dl/downloader/external.py
index b6601d7ba..b6e7bea07 100644
--- a/youtube_dl/downloader/external.py
+++ b/youtube_dl/downloader/external.py
@@ -305,7 +305,8 @@ class FFmpegFD(ExternalFD):
             else:
                 args += ['-f', 'mp4']
                 if tmpfilename == '-':
-                    args += ["-movflags", "frag_keyframe+empty_moov"]
+                    args += ['-movflags', 'frag_keyframe+empty_moov', '-c:v', 'libx264', '-c:a', 'aac', '-ac', '2', '-ab', '128000']
+                    args += ['-bsf:a', 'aac_adtstoasc', '-tune', 'zerolatency', '-preset', 'ultrafast', '-level', '31', '-pix_fmt', 'yuv420p']
                 if (ffpp.basename == 'ffmpeg' and is_outdated_version(ffpp._versions['ffmpeg'], '3.2', False)) and (not info_dict.get('acodec') or info_dict['acodec'].split('.')[0] in ('aac', 'mp4a')):
                     args += ['-bsf:a', 'aac_adtstoasc']
         elif protocol == 'rtmp':