avcodec: add option to make is_intra_more_likely() from error concealment return "no"

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

doc/codecs.texi

@@ -429,6 +429,8 @@ Possible values:
 iterative motion vector (MV) search (slow)
 @item deblock
 use strong deblock filter for damaged MBs
+@item favor_inter
+favor predicting from the previous frame instead of the current
 @end table
 
 @item bits_per_coded_sample @var{integer}

libavcodec/avcodec.h

@@ -2556,6 +2556,7 @@ typedef struct AVCodecContext {
     int error_concealment;
 #define FF_EC_GUESS_MVS   1
 #define FF_EC_DEBLOCK     2
+#define FF_EC_FAVOR_INTER 256
 
     /**
      * debug

libavcodec/error_resilience.c

@@ -686,6 +686,9 @@ static int is_intra_more_likely(ERContext *s)
     if (!s->last_pic.f || !s->last_pic.f->data[0])
         return 1; // no previous frame available -> use spatial prediction
 
+    if (s->avctx->error_concealment & FF_EC_FAVOR_INTER)
+        return 0;
+
     undamaged_count = 0;
     for (i = 0; i < s->mb_num; i++) {
         const int mb_xy = s->mb_index2xy[i];

libavcodec/options_table.h

@@ -223,6 +223,7 @@ static const AVOption avcodec_options[] = {
 {"ec", "set error concealment strategy", OFFSET(error_concealment), AV_OPT_TYPE_FLAGS, {.i64 = 3 }, INT_MIN, INT_MAX, V|D, "ec"},
 {"guess_mvs", "iterative motion vector (MV) search (slow)", 0, AV_OPT_TYPE_CONST, {.i64 = FF_EC_GUESS_MVS }, INT_MIN, INT_MAX, V|D, "ec"},
 {"deblock", "use strong deblock filter for damaged MBs", 0, AV_OPT_TYPE_CONST, {.i64 = FF_EC_DEBLOCK }, INT_MIN, INT_MAX, V|D, "ec"},
+{"favor_inter", "favor predicting from the previous frame", 0, AV_OPT_TYPE_CONST, {.i64 = FF_EC_FAVOR_INTER }, INT_MIN, INT_MAX, V|D, "ec"},
 {"bits_per_coded_sample", NULL, OFFSET(bits_per_coded_sample), AV_OPT_TYPE_INT, {.i64 = DEFAULT }, INT_MIN, INT_MAX},
 {"pred", "prediction method", OFFSET(prediction_method), AV_OPT_TYPE_INT, {.i64 = DEFAULT }, INT_MIN, INT_MAX, V|E, "pred"},
 {"left", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = FF_PRED_LEFT }, INT_MIN, INT_MAX, V|E, "pred"},

libavcodec/version.h

@@ -29,8 +29,8 @@
 #include "libavutil/version.h"
 
 #define LIBAVCODEC_VERSION_MAJOR 55
-#define LIBAVCODEC_VERSION_MINOR  60
-#define LIBAVCODEC_VERSION_MICRO 103
+#define LIBAVCODEC_VERSION_MINOR  61
+#define LIBAVCODEC_VERSION_MICRO 100
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
                                                LIBAVCODEC_VERSION_MINOR, \