avcodec/libvpxenc: use pix_fmt descriptors where useful

similar to:
36e51c190b avcodec/libaomenc: use pix_fmt descriptors where useful

Reviewed-by: James Almer <jamrial@gmail.com>
Signed-off-by: James Zern <jzern@google.com>

libavcodec/libvpxenc.c

@@ -41,6 +41,7 @@
 #include "libavutil/intreadwrite.h"
 #include "libavutil/mathematics.h"
 #include "libavutil/opt.h"
+#include "libavutil/pixdesc.h"
 
 /**
  * Portion of struct vpx_codec_cx_pkt from vpx_encoder.h.
@@ -546,7 +547,8 @@ static int set_pix_fmt(AVCodecContext *avctx, vpx_codec_caps_t codec_caps,
                        vpx_img_fmt_t *img_fmt)
 {
     VPxContext av_unused *ctx = avctx->priv_data;
-    enccfg->g_bit_depth = enccfg->g_input_bit_depth = 8;
+    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(avctx->pix_fmt);
+    enccfg->g_bit_depth = enccfg->g_input_bit_depth = desc->comp[0].depth;
     switch (avctx->pix_fmt) {
     case AV_PIX_FMT_YUV420P:
     case AV_PIX_FMT_YUVA420P:
@@ -570,8 +572,6 @@ static int set_pix_fmt(AVCodecContext *avctx, vpx_codec_caps_t codec_caps,
     case AV_PIX_FMT_YUV420P10:
     case AV_PIX_FMT_YUV420P12:
         if (codec_caps & VPX_CODEC_CAP_HIGHBITDEPTH) {
-            enccfg->g_bit_depth = enccfg->g_input_bit_depth =
-                avctx->pix_fmt == AV_PIX_FMT_YUV420P10 ? 10 : 12;
             enccfg->g_profile = 2;
             *img_fmt = VPX_IMG_FMT_I42016;
             *flags |= VPX_CODEC_USE_HIGHBITDEPTH;
@@ -581,8 +581,6 @@ static int set_pix_fmt(AVCodecContext *avctx, vpx_codec_caps_t codec_caps,
     case AV_PIX_FMT_YUV422P10:
     case AV_PIX_FMT_YUV422P12:
         if (codec_caps & VPX_CODEC_CAP_HIGHBITDEPTH) {
-            enccfg->g_bit_depth = enccfg->g_input_bit_depth =
-                avctx->pix_fmt == AV_PIX_FMT_YUV422P10 ? 10 : 12;
             enccfg->g_profile = 3;
             *img_fmt = VPX_IMG_FMT_I42216;
             *flags |= VPX_CODEC_USE_HIGHBITDEPTH;
@@ -592,8 +590,6 @@ static int set_pix_fmt(AVCodecContext *avctx, vpx_codec_caps_t codec_caps,
     case AV_PIX_FMT_YUV440P10:
     case AV_PIX_FMT_YUV440P12:
         if (codec_caps & VPX_CODEC_CAP_HIGHBITDEPTH) {
-            enccfg->g_bit_depth = enccfg->g_input_bit_depth =
-                avctx->pix_fmt == AV_PIX_FMT_YUV440P10 ? 10 : 12;
             enccfg->g_profile = 3;
             *img_fmt = VPX_IMG_FMT_I44016;
             *flags |= VPX_CODEC_USE_HIGHBITDEPTH;
@@ -606,9 +602,6 @@ static int set_pix_fmt(AVCodecContext *avctx, vpx_codec_caps_t codec_caps,
     case AV_PIX_FMT_YUV444P10:
     case AV_PIX_FMT_YUV444P12:
         if (codec_caps & VPX_CODEC_CAP_HIGHBITDEPTH) {
-            enccfg->g_bit_depth = enccfg->g_input_bit_depth =
-                avctx->pix_fmt == AV_PIX_FMT_YUV444P10 ||
-                avctx->pix_fmt == AV_PIX_FMT_GBRP10 ? 10 : 12;
             enccfg->g_profile = 3;
             *img_fmt = VPX_IMG_FMT_I44416;
             *flags |= VPX_CODEC_USE_HIGHBITDEPTH;