avcodec/sheervideo: Avoid code duplication when creating VLC tables

The SheerVideo decoder uses two VLC tables and these are in turn created
from structures (called SheerTable) that are naturally paired. This
commit unifies these pairs of SheerTables to arrays and unifies creating
the VLC tables.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

1 files changed, 28 insertions, 101 deletions

diff --git a/libavcodec/sheervideo.c b/libavcodec/sheervideo.c
index 3471fdcff9..976c21c445 100644
--- a/libavcodec/sheervideo.c
+++ b/libavcodec/sheervideo.c
@@ -1816,6 +1816,7 @@ static int decode_frame(AVCodecContext *avctx,
 {
     SheerVideoContext *s = avctx->priv_data;
     ThreadFrame frame = { .f = data };
+    const SheerTable *table;
     AVFrame *p = data;
     GetBitContext gb;
     unsigned format;
@@ -1835,210 +1836,135 @@ static int decode_frame(AVCodecContext *avctx,
     case MKTAG(' ', 'R', 'G', 'B'):
         avctx->pix_fmt = AV_PIX_FMT_RGB0;
         s->decode_frame = decode_rgb;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_r_rgb);
-            ret |= build_vlc(&s->vlc[1], &l_g_rgb);
-        }
+        table           = rgb;
         break;
     case MKTAG(' ', 'r', 'G', 'B'):
         avctx->pix_fmt = AV_PIX_FMT_RGB0;
         s->decode_frame = decode_rgbi;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_r_rgbi);
-            ret |= build_vlc(&s->vlc[1], &l_g_rgbi);
-        }
+        table           = rgbi;
         break;
     case MKTAG('A', 'R', 'G', 'X'):
         avctx->pix_fmt = AV_PIX_FMT_GBRAP10;
         s->decode_frame = decode_argx;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_r_rgbx);
-            ret |= build_vlc(&s->vlc[1], &l_g_rgbx);
-        }
+        table           = rgbx;
         break;
     case MKTAG('A', 'r', 'G', 'X'):
         avctx->pix_fmt = AV_PIX_FMT_GBRAP10;
         s->decode_frame = decode_argxi;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_r_rgbxi);
-            ret |= build_vlc(&s->vlc[1], &l_g_rgbxi);
-        }
+        table           = rgbxi;
         break;
     case MKTAG('R', 'G', 'B', 'X'):
         avctx->pix_fmt = AV_PIX_FMT_GBRP10;
         s->decode_frame = decode_rgbx;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_r_rgbx);
-            ret |= build_vlc(&s->vlc[1], &l_g_rgbx);
-        }
+        table           = rgbx;
         break;
     case MKTAG('r', 'G', 'B', 'X'):
         avctx->pix_fmt = AV_PIX_FMT_GBRP10;
         s->decode_frame = decode_rgbxi;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_r_rgbxi);
-            ret |= build_vlc(&s->vlc[1], &l_g_rgbxi);
-        }
+        table           = rgbxi;
         break;
     case MKTAG('A', 'R', 'G', 'B'):
         avctx->pix_fmt = AV_PIX_FMT_ARGB;
         s->decode_frame = decode_argb;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_r_rgb);
-            ret |= build_vlc(&s->vlc[1], &l_g_rgb);
-        }
+        table           = rgb;
         break;
     case MKTAG('A', 'r', 'G', 'B'):
         avctx->pix_fmt = AV_PIX_FMT_ARGB;
         s->decode_frame = decode_argbi;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_r_rgbi);
-            ret |= build_vlc(&s->vlc[1], &l_g_rgbi);
-        }
+        table           = rgbi;
         break;
     case MKTAG('A', 'Y', 'B', 'R'):
         s->alt = 1;
     case MKTAG('A', 'Y', 'b', 'R'):
         avctx->pix_fmt = AV_PIX_FMT_YUVA444P;
         s->decode_frame = decode_aybr;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_ybr);
-            ret |= build_vlc(&s->vlc[1], &l_u_ybr);
-        }
+        table           = ybr;
         break;
     case MKTAG('A', 'y', 'B', 'R'):
         s->alt = 1;
     case MKTAG('A', 'y', 'b', 'R'):
         avctx->pix_fmt = AV_PIX_FMT_YUVA444P;
         s->decode_frame = decode_aybri;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_ybri);
-            ret |= build_vlc(&s->vlc[1], &l_u_ybri);
-        }
+        table           = ybri;
         break;
     case MKTAG(' ', 'Y', 'B', 'R'):
         s->alt = 1;
     case MKTAG(' ', 'Y', 'b', 'R'):
         avctx->pix_fmt = AV_PIX_FMT_YUV444P;
         s->decode_frame = decode_ybr;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_ybr);
-            ret |= build_vlc(&s->vlc[1], &l_u_ybr);
-        }
+        table           = ybr;
         break;
     case MKTAG(' ', 'y', 'B', 'R'):
         s->alt = 1;
     case MKTAG(' ', 'y', 'b', 'R'):
         avctx->pix_fmt = AV_PIX_FMT_YUV444P;
         s->decode_frame = decode_ybri;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_ybri);
-            ret |= build_vlc(&s->vlc[1], &l_u_ybri);
-        }
+        table           = ybri;
         break;
     case MKTAG('Y', 'B', 'R', 0x0a):
         avctx->pix_fmt = AV_PIX_FMT_YUV444P10;
         s->decode_frame = decode_ybr10;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_ybr10);
-            ret |= build_vlc(&s->vlc[1], &l_u_ybr10);
-        }
+        table           = ybr10;
         break;
     case MKTAG('y', 'B', 'R', 0x0a):
         avctx->pix_fmt = AV_PIX_FMT_YUV444P10;
         s->decode_frame = decode_ybr10i;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_ybr10i);
-            ret |= build_vlc(&s->vlc[1], &l_u_ybr10i);
-        }
+        table           = ybr10i;
         break;
     case MKTAG('C', 'A', '4', 'p'):
         avctx->pix_fmt = AV_PIX_FMT_YUVA444P10;
         s->decode_frame = decode_ca4p;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_ybr10);
-            ret |= build_vlc(&s->vlc[1], &l_u_ybr10);
-        }
+        table           = ybr10;
         break;
     case MKTAG('C', 'A', '4', 'i'):
         avctx->pix_fmt = AV_PIX_FMT_YUVA444P10;
         s->decode_frame = decode_ca4i;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_ybr10i);
-            ret |= build_vlc(&s->vlc[1], &l_u_ybr10i);
-        }
+        table           = ybr10i;
         break;
     case MKTAG('B', 'Y', 'R', 'Y'):
         avctx->pix_fmt = AV_PIX_FMT_YUV422P;
         s->decode_frame = decode_byry;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_byry);
-            ret |= build_vlc(&s->vlc[1], &l_u_byry);
-        }
+        table           = byry;
         break;
     case MKTAG('B', 'Y', 'R', 'y'):
         avctx->pix_fmt = AV_PIX_FMT_YUV422P;
         s->decode_frame = decode_byryi;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_byryi);
-            ret |= build_vlc(&s->vlc[1], &l_u_byryi);
-        }
+        table           = byryi;
         break;
     case MKTAG('Y', 'b', 'Y', 'r'):
         avctx->pix_fmt = AV_PIX_FMT_YUV422P;
         s->decode_frame = decode_ybyr;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_ybyr);
-            ret |= build_vlc(&s->vlc[1], &l_u_ybyr);
-        }
+        table           = ybyr;
         break;
     case MKTAG('C', '8', '2', 'p'):
         avctx->pix_fmt = AV_PIX_FMT_YUVA422P;
         s->decode_frame = decode_c82p;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_byry);
-            ret |= build_vlc(&s->vlc[1], &l_u_byry);
-        }
+        table           = byry;
         break;
     case MKTAG('C', '8', '2', 'i'):
         avctx->pix_fmt = AV_PIX_FMT_YUVA422P;
         s->decode_frame = decode_c82i;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_byryi);
-            ret |= build_vlc(&s->vlc[1], &l_u_byryi);
-        }
+        table           = byryi;
         break;
     case MKTAG(0xa2, 'Y', 'R', 'Y'):
         avctx->pix_fmt = AV_PIX_FMT_YUV422P10;
         s->decode_frame = decode_yry10;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_yry10);
-            ret |= build_vlc(&s->vlc[1], &l_u_yry10);
-        }
+        table           = yry10;
         break;
     case MKTAG(0xa2, 'Y', 'R', 'y'):
         avctx->pix_fmt = AV_PIX_FMT_YUV422P10;
         s->decode_frame = decode_yry10i;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_yry10i);
-            ret |= build_vlc(&s->vlc[1], &l_u_yry10i);
-        }
+        table           = yry10i;
         break;
     case MKTAG('C', 'A', '2', 'p'):
         avctx->pix_fmt = AV_PIX_FMT_YUVA422P10;
         s->decode_frame = decode_ca2p;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_yry10);
-            ret |= build_vlc(&s->vlc[1], &l_u_yry10);
-        }
+        table           = yry10;
         break;
     case MKTAG('C', 'A', '2', 'i'):
         avctx->pix_fmt = AV_PIX_FMT_YUVA422P10;
         s->decode_frame = decode_ca2i;
-        if (s->format != format) {
-            ret  = build_vlc(&s->vlc[0], &l_y_yry10i);
-            ret |= build_vlc(&s->vlc[1], &l_u_yry10i);
-        }
+        table           = yry10i;
         break;
     default:
         avpriv_request_sample(avctx, "unsupported format: 0x%X", format);
@@ -2046,7 +1972,8 @@ static int decode_frame(AVCodecContext *avctx,
     }
 
     if (s->format != format) {
-        if (ret < 0) {
+        if ((ret = build_vlc(&s->vlc[0], &table[0])) < 0 ||
+            (ret = build_vlc(&s->vlc[1], &table[1])) < 0) {
             s->format = 0;
             return ret;
         }