<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta http-equiv="Content-Style-Type" content="text/css" />
<meta name="generator" content="pandoc" />
<title></title>
<style type="text/css">code{white-space: pre;}</style>
</head>
<body>
<p>Hi Steve,</p>
<p>I am not sure what the status for this patch is after <em>Remi’s</em> comments, I however wrote my reply prior to noticing that there was an on-going discussion, so I will send it to <code>vlc-devel</code> in either case.</p>
<p>On 2017-05-05 10:14, Steve Lhomme wrote:</p>
<blockquote style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;color:#500050">
<pre><code> Fixes #18078
---
modules/MODULES_LIST | 1 +
modules/video_filter/Makefile.am | 5 +-
modules/video_filter/chain.c | 216 +++++++++++++++++++++++++++++++++++++++
3 files changed, 221 insertions(+), 1 deletion(-)
create mode 100644 modules/video_filter/chain.c
diff --git a/modules/MODULES_LIST b/modules/MODULES_LIST
index 3205a0850b..b1d17da830 100644
--- a/modules/MODULES_LIST
+++ b/modules/MODULES_LIST
@@ -144,6 +144,7 @@ $Id$
* file_keystore: store secrets on a file, may use a submodule to crypt secrets
* file_logger: file logger plugin
* filesystem: Filesystem access module
+ * filterchain: Video filtering using intermediate converter modules
* fingerprinter: AcoustID audio fingerprinter using chromaprint
* flac: Flac decoder using libflac
* flacsys: FLAC demuxer
diff --git a/modules/video_filter/Makefile.am b/modules/video_filter/Makefile.am
index 8fcc93c4db..bf4b9ce9ad 100644
--- a/modules/video_filter/Makefile.am
+++ b/modules/video_filter/Makefile.am
@@ -67,6 +67,8 @@ libvhs_plugin_la_SOURCES = video_filter/vhs.c
libwave_plugin_la_SOURCES = video_filter/wave.c
libwave_plugin_la_LIBADD = $(LIBM)
+libfilterchain_plugin_la_SOURCES = video_filter/chain.c
+
video_filter_LTLIBRARIES = \
libadjust_plugin.la \
libalphamask_plugin.la \
@@ -105,7 +107,8 @@ video_filter_LTLIBRARIES = \
libfps_plugin.la \
libfreeze_plugin.la \
libpuzzle_plugin.la \
- librotate_plugin.la
+ librotate_plugin.la \
+ libfilterchain_plugin.la
libdeinterlace_plugin_la_SOURCES = \
video_filter/deinterlace/deinterlace.c video_filter/deinterlace/deinterlace.h \
diff --git a/modules/video_filter/chain.c b/modules/video_filter/chain.c
new file mode 100644
index 0000000000..b9ab7083e8
--- /dev/null
+++ b/modules/video_filter/chain.c
@@ -0,0 +1,216 @@
+/*****************************************************************************
+ * chain.c : chain multiple video filter modules as a last resort solution
+ *****************************************************************************
+ * Copyright (C) 2017 VLC authors, VideoLAN and VideoLabs
+ * $Id$
+ *
+ * Authors: Steve Lhomme <robux4@videolabs.io>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+ *****************************************************************************/
+
+/*****************************************************************************
+ * Preamble
+ *****************************************************************************/
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <vlc_common.h>
+#include <vlc_plugin.h>
+#include <vlc_filter.h>
+#include <vlc_picture.h>
+
+/*****************************************************************************
+ * Local prototypes.
+ *****************************************************************************/
+static const vlc_fourcc_t pi_allowed_chromas[] = {
+ VLC_CODEC_I420,
+ VLC_CODEC_I422,
+ VLC_CODEC_I420_10L,
+ VLC_CODEC_I420_16L,
+ VLC_CODEC_RGB32,
+ VLC_CODEC_RGB24,
+ 0
+};
+
+struct filter_sys_t
+{
+ filter_chain_t *p_chain;
+};
+
+/*****************************************************************************
+ * Buffer management
+ *****************************************************************************/
+static picture_t *BufferNew( filter_t *p_filter )
+{
+ filter_t *p_parent = p_filter->owner.sys;
+
+ return filter_NewPicture( p_parent );
+}
+
+#define CHAIN_LEVEL_MAX 1
+#define RECURSIVE_STRING (MODULE_STRING "-flevel")
+
+/*****************************************************************************
+ * Builders
+ *****************************************************************************/
+
+static int BuildShortcutChain( filter_t *p_filter )
+{
+ es_format_t fmt_mid;
+ int i_ret = VLC_EGENERIC;
+
+ /* Now try chroma format list */
+ for( int i = 0; pi_allowed_chromas[i]; i++ )
+ {
+ filter_chain_Reset( p_filter->p_sys->p_chain, &p_filter->fmt_in, &p_filter->fmt_out );
+
+ const vlc_fourcc_t i_chroma = pi_allowed_chromas[i];
+ if( i_chroma == p_filter->fmt_in.i_codec ||
+ i_chroma == p_filter->fmt_out.i_codec )
+ continue;
+
+ msg_Dbg( p_filter, "Trying to use chroma %4.4s as middle man",
+ (char*)&i_chroma );
+
+ es_format_Copy( &fmt_mid, &p_filter->fmt_in );
+ fmt_mid.i_codec =
+ fmt_mid.video.i_chroma = i_chroma;
+ fmt_mid.video.i_rmask = 0;
+ fmt_mid.video.i_gmask = 0;
+ fmt_mid.video.i_bmask = 0;
+ video_format_FixRgb(&fmt_mid.video);
+
+ if( filter_chain_AppendConverter( p_filter->p_sys->p_chain,
+ NULL, &fmt_mid ) == VLC_SUCCESS )
+ {
+ filter_t *found = filter_chain_AppendFilter( p_filter->p_sys->p_chain,
+ p_filter->shortcut,
+ p_filter->p_cfg, &fmt_mid,
+ &fmt_mid, true );
+ if (found != NULL)
+ {
+ if ( p_filter->b_allow_fmt_out_change ||
+ filter_chain_AppendConverter(p_filter->p_sys->p_chain, &fmt_mid,
+ &p_filter->fmt_out) == VLC_SUCCESS)
+ {
+ es_format_Clean( &fmt_mid );
+ i_ret = VLC_SUCCESS;
+ break;
+ }
+ }
+ }
+ es_format_Clean( &fmt_mid );
+ }
+ if (i_ret != VLC_SUCCESS)
+ filter_chain_Reset( p_filter->p_sys->p_chain, &p_filter->fmt_in, &p_filter->fmt_out );
+
+ var_Destroy( p_filter, RECURSIVE_STRING );
+ return i_ret;
+}
+
+/*****************************************************************************
+ * Chain
+ *****************************************************************************/
+static picture_t *Chain( filter_t *p_filter, picture_t *p_pic )
+{
+ return filter_chain_VideoFilter( p_filter->p_sys->p_chain, p_pic );
+}
+
+/*****************************************************************************
+ * Activate: allocate a chroma function
+ *****************************************************************************
+ * This function allocates and initializes a chroma function
+ *****************************************************************************/</code></pre>
</blockquote>
<p>Doxygen comments?</p>
<blockquote style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;color:#500050">
<pre><code> +static int Activate( vlc_object_t *p_this )
+{
+ filter_t *p_filter = (filter_t *)p_this;
+ filter_sys_t *p_sys;
+ int i_ret;
+
+ if (p_filter->shortcut == NULL)
+ return VLC_EGENERIC;
+
+ p_sys = p_filter->p_sys = calloc( 1, sizeof( *p_sys ) );
+ if( !p_sys )</code></pre>
</blockquote>
<p>As long as we have <code>unlikely</code> and <code>likely</code> in the codebase, I personally prefer us to use it where applicable.</p>
<blockquote style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;color:#500050">
<pre><code> + return VLC_ENOMEM;
+
+ filter_owner_t owner = {
+ .sys = p_filter,
+ .video = {
+ .buffer_new = BufferNew,
+ },
+ };
+
+ p_sys->p_chain = filter_chain_NewVideo( p_filter, false, &owner );
+ if( !p_sys->p_chain )
+ {
+ free( p_sys );
+ return VLC_EGENERIC;
+ }
+
+ int type = VLC_VAR_INTEGER;
+ if( var_Type( p_filter->obj.parent, RECURSIVE_STRING ) != 0 )
+ type |= VLC_VAR_DOINHERIT;
+
+ var_Create( p_filter, RECURSIVE_STRING, type );
+ /* Note: atomicity is not actually needed here. */
+ var_IncInteger( p_filter, RECURSIVE_STRING );
+
+ int level = var_GetInteger( p_filter, RECURSIVE_STRING );
+ if( level < 0 || level > CHAIN_LEVEL_MAX )
+ msg_Err( p_filter, "Too high level of recursion (%d)", level );
+ else
+ i_ret = BuildShortcutChain( p_filter );
+
+ if( i_ret )</code></pre>
</blockquote>
<p><code>i_ret</code> is potentially uninitialized (on error).</p>
<blockquote style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;color:#500050">
<pre><code> + {
+ /* Hum ... looks like this really isn't going to work. Too bad. */
+ var_Destroy( p_filter, RECURSIVE_STRING );
+ filter_chain_Delete( p_sys->p_chain );
+ free( p_sys );
+ return VLC_EGENERIC;
+ }
+
+ if ( p_filter->b_allow_fmt_out_change )
+ {
+ es_format_Clean( &p_filter->fmt_out );
+ es_format_Copy( &p_filter->fmt_out, filter_chain_GetFmtOut(p_sys->p_chain) );
+ }
+
+ /* */
+ p_filter->pf_video_filter = Chain;
+ return VLC_SUCCESS;
+}
+
+static void Destroy( vlc_object_t *p_this )
+{
+ filter_t *p_filter = (filter_t *)p_this;
+
+ var_Destroy( p_filter, RECURSIVE_STRING );
+ filter_chain_Delete( p_filter->p_sys->p_chain );
+ free( p_filter->p_sys );
+}
+
+/*****************************************************************************
+ * Module descriptor
+ *****************************************************************************/
+vlc_module_begin ()
+ set_description( N_("Video filter using a chain of video converter modules") )
+ set_capability( "video filter", 1 )
+ set_callbacks( Activate, Destroy )
+vlc_module_end ()</code></pre>
</blockquote>
</body>
</html>