swresample: Allow reinitialization without ever setting channel layouts

(cherry picked from commit 80a28c75)
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libswresample/options.c

@@ -51,10 +51,10 @@ static const AVOption options[]={
 {"out_sample_fmt"       , "set output sample format"    , OFFSET(out_sample_fmt ), AV_OPT_TYPE_SAMPLE_FMT , {.i64=AV_SAMPLE_FMT_NONE}, -1   , INT_MAX, PARAM},
 {"tsf"                  , "set internal sample format"  , OFFSET(int_sample_fmt ), AV_OPT_TYPE_SAMPLE_FMT , {.i64=AV_SAMPLE_FMT_NONE}, -1   , INT_MAX, PARAM},
 {"internal_sample_fmt"  , "set internal sample format"  , OFFSET(int_sample_fmt ), AV_OPT_TYPE_SAMPLE_FMT , {.i64=AV_SAMPLE_FMT_NONE}, -1   , INT_MAX, PARAM},
-{"icl"                  , "set input channel layout"    , OFFSET( in_ch_layout  ), AV_OPT_TYPE_CHANNEL_LAYOUT, {.i64=0                     }, 0      , INT64_MAX , PARAM, "channel_layout"},
-{"in_channel_layout"    , "set input channel layout"    , OFFSET( in_ch_layout  ), AV_OPT_TYPE_CHANNEL_LAYOUT, {.i64=0                     }, 0      , INT64_MAX , PARAM, "channel_layout"},
-{"ocl"                  , "set output channel layout"   , OFFSET(out_ch_layout  ), AV_OPT_TYPE_CHANNEL_LAYOUT, {.i64=0                     }, 0      , INT64_MAX , PARAM, "channel_layout"},
-{"out_channel_layout"   , "set output channel layout"   , OFFSET(out_ch_layout  ), AV_OPT_TYPE_CHANNEL_LAYOUT, {.i64=0                     }, 0      , INT64_MAX , PARAM, "channel_layout"},
+{"icl"                  , "set input channel layout"    , OFFSET(user_in_ch_layout ), AV_OPT_TYPE_CHANNEL_LAYOUT, {.i64=0           }, 0    , INT64_MAX , PARAM, "channel_layout"},
+{"in_channel_layout"    , "set input channel layout"    , OFFSET(user_in_ch_layout ), AV_OPT_TYPE_CHANNEL_LAYOUT, {.i64=0           }, 0    , INT64_MAX , PARAM, "channel_layout"},
+{"ocl"                  , "set output channel layout"   , OFFSET(user_out_ch_layout), AV_OPT_TYPE_CHANNEL_LAYOUT, {.i64=0           }, 0    , INT64_MAX , PARAM, "channel_layout"},
+{"out_channel_layout"   , "set output channel layout"   , OFFSET(user_out_ch_layout), AV_OPT_TYPE_CHANNEL_LAYOUT, {.i64=0           }, 0    , INT64_MAX , PARAM, "channel_layout"},
 {"clev"                 , "set center mix level"        , OFFSET(clev           ), AV_OPT_TYPE_FLOAT, {.dbl=C_30DB                }, -32    , 32        , PARAM},
 {"center_mix_level"     , "set center mix level"        , OFFSET(clev           ), AV_OPT_TYPE_FLOAT, {.dbl=C_30DB                }, -32    , 32        , PARAM},
 {"slev"                 , "set surround mix level"      , OFFSET(slev           ), AV_OPT_TYPE_FLOAT, {.dbl=C_30DB                }, -32    , 32        , PARAM},

libswresample/rematrix.c

@@ -65,8 +65,8 @@ int swr_set_matrix(struct SwrContext *s, const double *matrix, int stride)
     if (!s || s->in_convert) // s needs to be allocated but not initialized
         return AVERROR(EINVAL);
     memset(s->matrix, 0, sizeof(s->matrix));
-    nb_in  = av_get_channel_layout_nb_channels(s->in_ch_layout);
-    nb_out = av_get_channel_layout_nb_channels(s->out_ch_layout);
+    nb_in  = av_get_channel_layout_nb_channels(s->user_in_ch_layout);
+    nb_out = av_get_channel_layout_nb_channels(s->user_out_ch_layout);
     for (out = 0; out < nb_out; out++) {
         for (in = 0; in < nb_in; in++)
             s->matrix[out][in] = matrix[in];

libswresample/swresample.c

@@ -86,10 +86,10 @@ struct SwrContext *swr_alloc_set_opts(struct SwrContext *s,
     if (av_opt_set_int(s, "tsf", AV_SAMPLE_FMT_NONE,   0) < 0)
         goto fail;
 
-    if (av_opt_set_int(s, "ich", av_get_channel_layout_nb_channels(s-> in_ch_layout), 0) < 0)
+    if (av_opt_set_int(s, "ich", av_get_channel_layout_nb_channels(s-> user_in_ch_layout), 0) < 0)
         goto fail;
 
-    if (av_opt_set_int(s, "och", av_get_channel_layout_nb_channels(s->out_ch_layout), 0) < 0)
+    if (av_opt_set_int(s, "och", av_get_channel_layout_nb_channels(s->user_out_ch_layout), 0) < 0)
         goto fail;
 
     av_opt_set_int(s, "uch", 0, 0);
@@ -168,6 +168,9 @@ av_cold int swr_init(struct SwrContext *s){
     s-> in.ch_count  = s->  user_in_ch_count;
     s->used_ch_count = s->user_used_ch_count;
 
+    s-> in_ch_layout = s-> user_in_ch_layout;
+    s->out_ch_layout = s->user_out_ch_layout;
+
     if(av_get_channel_layout_nb_channels(s-> in_ch_layout) > SWR_CH_MAX) {
         av_log(s, AV_LOG_WARNING, "Input channel layout 0x%"PRIx64" is invalid or unsupported.\n", s-> in_ch_layout);
         s->in_ch_layout = 0;

libswresample/swresample_internal.h

@@ -93,6 +93,8 @@ struct SwrContext {
     int user_in_ch_count;                           ///< User set input channel count
     int user_out_ch_count;                          ///< User set output channel count
     int user_used_ch_count;                         ///< User set used channel count
+    int64_t user_in_ch_layout;                      ///< User set input channel layout
+    int64_t user_out_ch_layout;                     ///< User set output channel layout
 
     struct DitherContext dither;