X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fsvq1dec.c;h=7aea1380604b853a1b4c446f8a847820bcfecc0c;hb=e27466d7e59f0a485f3720f33cd9c54d69fff138;hp=d3e60c3a4ab08f97fb2dc3979fcc22289b639b15;hpb=ace96d2e693d804a0ed16aebc1b1027cfff2c527;p=ffmpeg

diff --git a/libavcodec/svq1dec.c b/libavcodec/svq1dec.c
index d3e60c3a4ab..7aea1380604 100644
--- a/libavcodec/svq1dec.c
+++ b/libavcodec/svq1dec.c
@@ -32,6 +32,9 @@
  *   http://www.pcisys.net/~melanson/codecs/
  */
 
+#include "libavutil/crc.h"
+#include "libavutil/thread.h"
+
 #include "avcodec.h"
 #include "get_bits.h"
 #include "h263.h"
@@ -546,9 +549,7 @@ static int svq1_decode_frame_header(AVCodecContext *avctx, AVFrame *frame)
         if (s->frame_code == 0x50 || s->frame_code == 0x60) {
             int csum = get_bits(bitbuf, 16);
 
-            csum = ff_svq1_packet_checksum(bitbuf->buffer,
-                                           bitbuf->size_in_bits >> 3,
-                                           csum);
+            csum = av_bswap16(av_crc(av_crc_get_table(AV_CRC_16_CCITT), av_bswap16(csum), bitbuf->buffer, bitbuf->size_in_bits >> 3));
 
             ff_dlog(avctx, "%s checksum (%02x) for packet data\n",
                     (csum == 0) ? "correct" : "incorrect", csum);
@@ -602,6 +603,8 @@ static int svq1_decode_frame_header(AVCodecContext *avctx, AVFrame *frame)
         if (skip_1stop_8data_bits(bitbuf) < 0)
             return AVERROR_INVALIDDATA;
     }
+    if (get_bits_left(bitbuf) <= 0)
+        return AVERROR_INVALIDDATA;
 
     s->width  = width;
     s->height = height;
@@ -677,7 +680,7 @@ static int svq1_decode_frame(AVCodecContext *avctx, void *data,
     if (result < 0)
         return result;
 
-    pmv = av_malloc((FFALIGN(s->width, 16) / 8 + 3) * sizeof(*pmv));
+    pmv = av_malloc_array(FFALIGN(s->width, 16) / 8 + 3, sizeof(*pmv));
     if (!pmv)
         return AVERROR(ENOMEM);
 
@@ -760,22 +763,8 @@ err:
     return result;
 }
 
-static av_cold int svq1_decode_init(AVCodecContext *avctx)
+static av_cold void svq1_static_init(void)
 {
-    SVQ1Context *s = avctx->priv_data;
-    int i;
-    int offset = 0;
-
-    s->prev = av_frame_alloc();
-    if (!s->prev)
-        return AVERROR(ENOMEM);
-
-    s->width            = avctx->width  + 3 & ~3;
-    s->height           = avctx->height + 3 & ~3;
-    avctx->pix_fmt      = AV_PIX_FMT_YUV410P;
-
-    ff_hpeldsp_init(&s->hdsp, avctx->flags);
-
     INIT_VLC_STATIC(&svq1_block_type, 2, 4,
                     &ff_svq1_block_type_vlc[0][1], 2, 1,
                     &ff_svq1_block_type_vlc[0][0], 2, 1, 6);
@@ -784,7 +773,7 @@ static av_cold int svq1_decode_init(AVCodecContext *avctx)
                     &ff_mvtab[0][1], 2, 1,
                     &ff_mvtab[0][0], 2, 1, 176);
 
-    for (i = 0; i < 6; i++) {
+    for (int i = 0, offset = 0; i < 6; i++) {
         static const uint8_t sizes[2][6] = { { 14, 10, 14, 18, 16, 18 },
                                              { 10, 10, 14, 14, 14, 16 } };
         static VLC_TYPE table[168][2];
@@ -811,6 +800,24 @@ static av_cold int svq1_decode_init(AVCodecContext *avctx)
     INIT_VLC_STATIC(&svq1_inter_mean, 9, 512,
                     &ff_svq1_inter_mean_vlc[0][1], 4, 2,
                     &ff_svq1_inter_mean_vlc[0][0], 4, 2, 1434);
+}
+
+static av_cold int svq1_decode_init(AVCodecContext *avctx)
+{
+    static AVOnce init_static_once = AV_ONCE_INIT;
+    SVQ1Context *s = avctx->priv_data;
+
+    s->prev = av_frame_alloc();
+    if (!s->prev)
+        return AVERROR(ENOMEM);
+
+    s->width            = avctx->width  + 3 & ~3;
+    s->height           = avctx->height + 3 & ~3;
+    avctx->pix_fmt      = AV_PIX_FMT_YUV410P;
+
+    ff_hpeldsp_init(&s->hdsp, avctx->flags);
+
+    ff_thread_once(&init_static_once, svq1_static_init);
 
     return 0;
 }
@@ -846,4 +853,5 @@ AVCodec ff_svq1_decoder = {
     .flush          = svq1_flush,
     .pix_fmts       = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV410P,
                                                      AV_PIX_FMT_NONE },
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
 };