[FFmpeg-devel] [PATCH] libavcodec: add tune_content option also for VP8.

[Dariusz Marcinkiewicz]

This exposes VP8E_SET_SCREEN_CONTENT_MODE option from libvpx.

Change authored by Erik Språng <sprang at webrtc.org>

Signed-off-by: Dariusz Marcinkiewicz <darekm at google.com>
---
 doc/encoders.texi      |  7 +++++--
 libavcodec/libvpxenc.c | 35 ++++++++++++++++++++++++++++++++++-
 2 files changed, 39 insertions(+), 3 deletions(-)

diff --git a/doc/encoders.texi b/doc/encoders.texi
index c9fe6d6143..2a9b38f62a 100644
--- a/doc/encoders.texi
+++ b/doc/encoders.texi
@@ -2186,6 +2186,11 @@ Enable error resiliency features.
 Increase sharpness at the expense of lower PSNR.
 The valid range is [0, 7].
 
+ at item tune-content
+Set content type.
+For VP8: default (0), screen (1), screen with aggressive rate control (2).
+For VP9: default (0), screen (1), film (2).
+
 @item ts-parameters
 Sets the temporal scalability configuration using a :-separated list of
 key=value pairs. For example, to specify temporal scalability parameters
@@ -2268,8 +2273,6 @@ colorspaces:
 @end table
 @item row-mt @var{boolean}
 Enable row based multi-threading.
- at item tune-content
-Set content type: default (0), screen (1), film (2).
 @item corpus-complexity
 Corpus VBR mode is a variant of standard VBR where the complexity distribution
 midpoint is passed in rather than calculated for a specific clip or chunk.
diff --git a/libavcodec/libvpxenc.c b/libavcodec/libvpxenc.c
index 80988a2608..c28cca40a2 100644
--- a/libavcodec/libvpxenc.c
+++ b/libavcodec/libvpxenc.c
@@ -164,6 +164,7 @@ static const char *const ctlidstr[] = {
     [VP8E_SET_MAX_INTRA_BITRATE_PCT] = "VP8E_SET_MAX_INTRA_BITRATE_PCT",
     [VP8E_SET_SHARPNESS]               = "VP8E_SET_SHARPNESS",
     [VP8E_SET_TEMPORAL_LAYER_ID]       = "VP8E_SET_TEMPORAL_LAYER_ID",
+    [VP8E_SET_SCREEN_CONTENT_MODE]     = "VP8E_SET_SCREEN_CONTENT_MODE",
 #if CONFIG_LIBVPX_VP9_ENCODER
     [VP9E_SET_LOSSLESS]                = "VP9E_SET_LOSSLESS",
     [VP9E_SET_TILE_COLUMNS]            = "VP9E_SET_TILE_COLUMNS",
@@ -1249,8 +1250,19 @@ static av_cold int vpx_init(AVCodecContext *avctx,
             codecctl_int(avctx, VP9E_SET_ROW_MT, ctx->row_mt);
 #endif
 #ifdef VPX_CTRL_VP9E_SET_TUNE_CONTENT
-        if (ctx->tune_content >= 0)
+        if (ctx->tune_content >= 0 && avctx->codec_id == AV_CODEC_ID_VP9) {
             codecctl_int(avctx, VP9E_SET_TUNE_CONTENT, ctx->tune_content);
+        }
+#endif
+#ifdef VPX_CTRL_VP8E_SET_SCREEN_CONTENT_MODE
+        if (ctx->tune_content >= 0 && avctx->codec_id == AV_CODEC_ID_VP8) {
+          if (ctx->tune_content == 2 && ctx->is_alpha) {
+            av_log(avctx, AV_LOG_ERROR,
+                   "Transparency encoding with screen mode with aggressive rate control not supported\n");
+            return AVERROR(EINVAL);
+          }
+          codecctl_int(avctx, VP8E_SET_SCREEN_CONTENT_MODE, ctx->tune_content);
+        }
 #endif
 #ifdef VPX_CTRL_VP9E_SET_TPL
         if (ctx->tpl_model >= 0)
@@ -1857,6 +1869,21 @@ FF_ENABLE_DEPRECATION_WARNINGS
     }
 
     coded_size = queue_frames(avctx, &ctx->encoder, &ctx->coded_frame_list, pkt);
+    if (avctx->codec_id == AV_CODEC_ID_VP8 && coded_size == 0 && ctx->tune_content == 2) {
+        // VP8 tuned for screen content with aggresive rate control - returned
+        // OK status code but produced no output, this indicates frame was
+        // rolled back due to bitrate overshoot - try to encode it again.
+        av_log(avctx, AV_LOG_VERBOSE,
+               "Attempting to reencode dropped VP8 screencast frame.");
+        res = vpx_codec_encode(&ctx->encoder, rawimg, timestamp,
+                               avctx->ticks_per_frame, flags, ctx->deadline);
+        if (res != VPX_CODEC_OK) {
+            log_encoder_error(avctx, "Error encoding frame");
+            return AVERROR_INVALIDDATA;
+        }
+        coded_size = queue_frames(avctx, &ctx->encoder, &ctx->coded_frame_list, pkt);
+    }
+
     if (ctx->is_alpha) {
         queue_frames(avctx, &ctx->encoder_alpha, &ctx->alpha_coded_frame_list, NULL);
 
@@ -1946,6 +1973,12 @@ static const AVOption vp8_options[] = {
     { "auto-alt-ref",    "Enable use of alternate reference "
                          "frames (2-pass only)",                        OFFSET(auto_alt_ref),    AV_OPT_TYPE_INT, {.i64 = -1}, -1,  2, VE},
     { "cpu-used",        "Quality/Speed ratio modifier",                OFFSET(cpu_used),        AV_OPT_TYPE_INT, {.i64 = 1}, -16, 16, VE},
+    { "tune-content",     "Tune content type",                          OFFSET(tune_content),    AV_OPT_TYPE_INT, {.i64 = -1}, -1,  2, VE, "tune_content"},
+#ifdef VPX_CTRL_VP8E_SET_SCREEN_CONTENT_MODE
+    { "default",          "Regular video content",                      0,                       AV_OPT_TYPE_CONST, {.i64 = 0}, 0,  0, VE, "tune_content"},
+    { "screen",           "Screen content mode on",                     0,                       AV_OPT_TYPE_CONST, {.i64 = 1}, 0,  0, VE, "tune_content"},
+    { "screen-rate-control", "Screen content mode with aggressive rate control", 0,              AV_OPT_TYPE_CONST, {.i64 = 2}, 0,  0, VE, "tune_content"},
+#endif
     LEGACY_OPTIONS
     { NULL }
 };
-- 
2.43.0.429.g432eaa2c6b-goog