vp9_parse: fix parsing of pskip and profile 2/3.

The fate results change because we now correctly timestamp the pskip
frames, which means the results are now identical to -vsync 0.

libavcodec/vp9_parser.c

@@ -22,6 +22,7 @@
  */
 
 #include "libavutil/intreadwrite.h"
+#include "libavcodec/get_bits.h"
 #include "parser.h"
 
 typedef struct VP9ParseContext {
@@ -30,11 +31,28 @@ typedef struct VP9ParseContext {
     int64_t pts;
 } VP9ParseContext;
 
-static void parse_frame(AVCodecParserContext *ctx, const uint8_t *buf, int size)
+static int parse_frame(AVCodecParserContext *ctx, const uint8_t *buf, int size)
 {
     VP9ParseContext *s = ctx->priv_data;
+    GetBitContext gb;
+    int res, profile, keyframe, invisible;
+
+    if ((res = init_get_bits8(&gb, buf, size)) < 0)
+        return res;
+    get_bits(&gb, 2); // frame marker
+    profile  = get_bits1(&gb);
+    profile |= get_bits1(&gb) << 1;
+    if (profile == 3) profile += get_bits1(&gb);
+
+    if (get_bits1(&gb)) {
+        keyframe = 0;
+        invisible = 0;
+    } else {
+        keyframe  = !get_bits1(&gb);
+        invisible = !get_bits1(&gb);
+    }
 
-    if (buf[0] & 0x4) {
+    if (!keyframe) {
         ctx->pict_type = AV_PICTURE_TYPE_P;
         ctx->key_frame = 0;
     } else {
@@ -42,7 +60,7 @@ static void parse_frame(AVCodecParserContext *ctx, const uint8_t *buf, int size)
         ctx->key_frame = 1;
     }
 
-    if (buf[0] & 0x2) {
+    if (!invisible) {
         if (ctx->pts == AV_NOPTS_VALUE)
             ctx->pts = s->pts;
         s->pts = AV_NOPTS_VALUE;
@@ -50,6 +68,8 @@ static void parse_frame(AVCodecParserContext *ctx, const uint8_t *buf, int size)
         s->pts = ctx->pts;
         ctx->pts = AV_NOPTS_VALUE;
     }
+
+    return 0;
 }
 
 static int parse(AVCodecParserContext *ctx,

tests/ref/fate/vp9-10-show-existing-frame

@@ -5,10 +5,14 @@
 #stream#, dts,        pts, duration,     size, hash
 0,          0,          0,        1,   152064, 18981342ec178e082519451062c3a67f
 0,          1,          1,        1,   152064, 04ab9dbeac49ec31be58f6e671698e05
+0,          4,          4,        1,   152064, 4ed58a0ba93a5d97a232a50c5876cda2
 0,          6,          6,        1,   152064, a41f00034923e56ba51a0b598acc2e3a
 0,          7,          7,        1,   152064, 63fa55ae9535ccdf06d44cce8065dda6
+0,          8,          8,        1,   152064, a41f00034923e56ba51a0b598acc2e3a
 0,          9,          9,        1,   152064, 0e4b08e14d919edee2bbff2ecd47de57
-0,         10,         10,        1,   152064, 0e4b08e14d919edee2bbff2ecd47de57
+0,         11,         11,        1,   152064, 0e4b08e14d919edee2bbff2ecd47de57
+0,         12,         12,        1,   152064, 5d4af03fc3d410413ef2b5a6275528b7
 0,         13,         13,        1,   152064, 9e932915c67a789f6877e6d3f76d3649
 0,         14,         14,        1,   152064, 12f2e975c217e7ffcf334524e8acec35
 0,         15,         15,        1,   152064, 9e932915c67a789f6877e6d3f76d3649
+0,         16,         16,        1,   152064, 12f2e975c217e7ffcf334524e8acec35

tests/ref/fate/vp9-10-show-existing-frame2

@@ -15,6 +15,7 @@
 0,          9,          9,        1,   152064, 7dc65a2af108379f2b9265a9a1ea7cf8
 0,         10,         10,        1,   152064, c979e2f084760775a567f60f79f28198
 0,         11,         11,        1,   152064, fe668a6417aa0543e4ed4d1c67c5cbcb
+0,         12,         12,        1,   152064, bf9901e39815fa93cce0ed5b02b2ef2d
 0,         13,         13,        1,   152064, 627466200370e6ad60ea570d31be66e3
 0,         14,         14,        1,   152064, 7dc65a2af108379f2b9265a9a1ea7cf8
 0,         15,         15,        1,   152064, c979e2f084760775a567f60f79f28198

tests/ref/fate/vp9-16-intra-only

@@ -6,5 +6,7 @@
 0,          0,          0,        1,   152064, d57529601178948afa4818c3c8938884
 0,          1,          1,        1,   152064, d47e00250c45733d64af067a417bcd06
 0,          2,          2,        1,   152064, 984e41cd8350808ac6129746b2377818
-0,          4,          4,        1,   152064, 76ba63001170b8992fc72be5c4ace731
-0,          5,          5,        1,   152064, c4e7f96a8fd58d901b1d881926ddae09
+0,          3,          3,        1,   152064, a5fa62996b4bb52e72e335722cf55bef
+0,          4,          4,        1,   152064, b71ca5ad650170ac921a71a6440fb508
+0,          5,          5,        1,   152064, 76ba63001170b8992fc72be5c4ace731
+0,          6,          6,        1,   152064, c4e7f96a8fd58d901b1d881926ddae09