add initial QP value options

Signed-off-by: Diego Biurrun <diego@biurrun.de>

libavcodec/nvenc.c

@@ -519,6 +519,8 @@ static void set_constqp(AVCodecContext *avctx, NV_ENC_RC_PARAMS *rc)
 
 static void set_vbr(AVCodecContext *avctx, NV_ENC_RC_PARAMS *rc)
 {
+    NVENCContext *ctx    = avctx->priv_data;
+
     if (avctx->qmin >= 0) {
         rc->enableMinQP    = 1;
         rc->minQP.qpInterB = avctx->qmin;
@@ -532,6 +534,30 @@ static void set_vbr(AVCodecContext *avctx, NV_ENC_RC_PARAMS *rc)
         rc->maxQP.qpInterP = avctx->qmax;
         rc->maxQP.qpIntra  = avctx->qmax;
     }
+
+    if (ctx->init_qp_p >= 0) {
+        rc->enableInitialRCQP = 1;
+        rc->initialRCQP.qpInterP = ctx->init_qp_p;
+        if (ctx->init_qp_i < 0) {
+            if (avctx->i_quant_factor != 0.0 && avctx->b_quant_factor != 0.0) {
+                rc->initialRCQP.qpIntra = av_clip(rc->initialRCQP.qpInterP * fabs(avctx->i_quant_factor) + avctx->i_quant_offset + 0.5, 0, 51);
+            } else {
+                rc->initialRCQP.qpIntra = rc->initialRCQP.qpInterP;
+            }
+        } else {
+            rc->initialRCQP.qpIntra = ctx->init_qp_i;
+        }
+
+        if (ctx->init_qp_b < 0) {
+            if (avctx->i_quant_factor != 0.0 && avctx->b_quant_factor != 0.0) {
+                rc->initialRCQP.qpInterB = av_clip(rc->initialRCQP.qpInterP * fabs(avctx->b_quant_factor) + avctx->b_quant_offset + 0.5, 0, 51);
+            } else {
+                rc->initialRCQP.qpInterB = rc->initialRCQP.qpInterP;
+            }
+        } else {
+            rc->initialRCQP.qpInterB = ctx->init_qp_b;
+        }
+    }
 }
 
 static void set_lossless(AVCodecContext *avctx, NV_ENC_RC_PARAMS *rc)

libavcodec/nvenc.h

@@ -183,6 +183,9 @@ typedef struct NVENCContext {
     int strict_gop;
     int aq_strength;
     int quality;
+    int init_qp_p;
+    int init_qp_b;
+    int init_qp_i;
 } NVENCContext;
 
 int ff_nvenc_encode_init(AVCodecContext *avctx);

libavcodec/nvenc_h264.c

@@ -89,6 +89,9 @@ static const AVOption options[] = {
     { "aq-strength", "When Spatial AQ is enabled, this field is used to specify AQ strength. AQ strength scale is from 1 (low) - 15 (aggressive)", OFFSET(aq_strength), AV_OPT_TYPE_INT, { .i64 = 8 }, 1, 15, VE },
     { "cq", "Set target quality level (0 to 51, 0 means automatic) for constant quality mode in VBR rate control", OFFSET(quality), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 51, VE },
 #endif /* NVENCAPI_MAJOR_VERSION >= 7 */
+    { "init_qpP", "Initial QP value for P-frames",        OFFSET(init_qp_p),   AV_OPT_TYPE_INT,    { .i64 = -1 }, -1, 51, VE },
+    { "init_qpB", "Initial QP value for B-frames",        OFFSET(init_qp_b),   AV_OPT_TYPE_INT,    { .i64 = -1 }, -1, 51, VE },
+    { "init_qpI", "Initial QP value for I-frames",        OFFSET(init_qp_i),   AV_OPT_TYPE_INT,    { .i64 = -1 }, -1, 51, VE },
     { NULL }
 };
 

libavcodec/nvenc_hevc.c

@@ -87,6 +87,9 @@ static const AVOption options[] = {
     { "aq-strength", "When Spatial AQ is enabled, this field is used to specify AQ strength. AQ strength scale is from 1 (low) - 15 (aggressive)", OFFSET(aq_strength), AV_OPT_TYPE_INT, { .i64 = 8 }, 1, 15, VE },
     { "cq", "Set target quality level (0 to 51, 0 means automatic) for constant quality mode in VBR rate control", OFFSET(quality), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 51, VE },
 #endif /* NVENCAPI_MAJOR_VERSION >= 7 */
+    { "init_qpP", "Initial QP value for P-frames",        OFFSET(init_qp_p),   AV_OPT_TYPE_INT,    { .i64 = -1 }, -1, 51, VE },
+    { "init_qpB", "Initial QP value for B-frames",        OFFSET(init_qp_b),   AV_OPT_TYPE_INT,    { .i64 = -1 }, -1, 51, VE },
+    { "init_qpI", "Initial QP value for I-frames",        OFFSET(init_qp_i),   AV_OPT_TYPE_INT,    { .i64 = -1 }, -1, 51, VE },
     { NULL }
 };