Give more meaningful message on BMP header parsing error

[ffmpeg] / libavcodec / mdec.c

diff --git a/libavcodec/mdec.c b/libavcodec/mdec.c
index 9053f487100f78fb41a6d2028234e8b590593e9a..37457676a66d8ce28fbac4f537f0673f29ddfab6 100644 (file)
--- a/libavcodec/mdec.c
+++ b/libavcodec/mdec.c
@@ -1,5 +1,5 @@
 /*
- * PSX MDEC codec
+ * Sony PlayStation MDEC (Motion DECoder)
  * Copyright (c) 2003 Michael Niedermayer
  *
  * based upon code from Sebastian Jedruszkiewicz <elf@frogger.rules.pl>
@@ -23,22 +23,19 @@
 
 /**
  * @file mdec.c
- * PSX MDEC codec.
- * This is very similar to intra only MPEG1.
+ * Sony PlayStation MDEC (Motion DECoder)
+ * This is very similar to intra-only MPEG-1.
  */
 
 #include "avcodec.h"
 #include "dsputil.h"
 #include "mpegvideo.h"
-
-//#undef NDEBUG
-//#include <assert.h>
+#include "mpeg12.h"
 
 typedef struct MDECContext{
     AVCodecContext *avctx;
     DSPContext dsp;
     AVFrame picture;
-    PutBitContext pb;
     GetBitContext gb;
     ScanTable scantable;
     int version;
@@ -55,7 +52,7 @@ typedef struct MDECContext{
     int block_last_index[6];
 } MDECContext;
 
-//very similar to mpeg1
+//very similar to MPEG-1
 static inline int mdec_decode_block_intra(MDECContext *a, DCTELEM *block, int n)
 {
     int level, diff, i, j, run;
@@ -65,7 +62,7 @@ static inline int mdec_decode_block_intra(MDECContext *a, DCTELEM *block, int n)
     const uint16_t *quant_matrix= ff_mpeg1_default_intra_matrix;
     const int qscale= a->qscale;
 
-    /* DC coef */
+    /* DC coefficient */
     if(a->version==2){
         block[0]= 2*get_sbits(&a->gb, 10) + 1024;
     }else{
@@ -80,7 +77,7 @@ static inline int mdec_decode_block_intra(MDECContext *a, DCTELEM *block, int n)
     i = 0;
     {
         OPEN_READER(re, &a->gb);
-        /* now quantify & encode AC coefs */
+        /* now quantify & encode AC coefficients */
         for(;;) {
             UPDATE_CACHE(re, &a->gb);
             GET_RL_VLC(level, run, re, &a->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
@@ -91,7 +88,6 @@ static inline int mdec_decode_block_intra(MDECContext *a, DCTELEM *block, int n)
                 i += run;
                 j = scantable[i];
                 level= (level*qscale*quant_matrix[j])>>3;
-//                level= (level-1)|1;
                 level = (level ^ SHOW_SBITS(re, &a->gb, 1)) - SHOW_SBITS(re, &a->gb, 1);
                 LAST_SKIP_BITS(re, &a->gb, 1);
             } else {
@@ -162,7 +158,7 @@ static int decode_frame(AVCodecContext *avctx,
 {
     MDECContext * const a = avctx->priv_data;
     AVFrame *picture = data;
-    AVFrame * const p= (AVFrame*)&a->picture;
+    AVFrame * const p= &a->picture;
     int i;
 
     if(p->data[0])
@@ -193,8 +189,6 @@ static int decode_frame(AVCodecContext *avctx,
     a->last_dc[1]=
     a->last_dc[2]= 128;
 
-//    printf("qscale:%d (0x%X), version:%d (0x%X)\n", a->qscale, a->qscale, a->version, a->version);
-
     for(a->mb_x=0; a->mb_x<a->mb_width; a->mb_x++){
         for(a->mb_y=0; a->mb_y<a->mb_height; a->mb_y++){
             if( decode_mb(a, a->block) <0)
@@ -204,14 +198,12 @@ static int decode_frame(AVCodecContext *avctx,
         }
     }
 
-//    p->quality= (32 + a->inv_qscale/2)/a->inv_qscale;
-//    memset(p->qscale_table, p->quality, p->qstride*a->mb_height);
+    p->quality= a->qscale * FF_QP2LAMBDA;
+    memset(p->qscale_table, a->qscale, p->qstride*a->mb_height);
 
-    *picture= *(AVFrame*)&a->picture;
+    *picture   = a->picture;
     *data_size = sizeof(AVPicture);
 
-    emms_c();
-
     return (get_bits_count(&a->gb)+31)/32*4;
 }
 
@@ -223,23 +215,18 @@ static av_cold void mdec_common_init(AVCodecContext *avctx){
     a->mb_width   = (avctx->coded_width  + 15) / 16;
     a->mb_height  = (avctx->coded_height + 15) / 16;
 
-    avctx->coded_frame= (AVFrame*)&a->picture;
+    avctx->coded_frame= &a->picture;
     a->avctx= avctx;
 }
 
 static av_cold int decode_init(AVCodecContext *avctx){
     MDECContext * const a = avctx->priv_data;
-    AVFrame *p= (AVFrame*)&a->picture;
+    AVFrame *p= &a->picture;
 
     mdec_common_init(avctx);
-    init_vlcs();
+    ff_mpeg12_init_vlcs();
     ff_init_scantable(a->dsp.idct_permutation, &a->scantable, ff_zigzag_direct);
-/*
-    for(i=0; i<64; i++){
-        int index= ff_zigzag_direct[i];
-        a->intra_matrix[i]= 64*ff_mpeg1_default_intra_matrix[index] / a->inv_qscale;
-    }
-*/
+
     p->qstride= a->mb_width;
     p->qscale_table= av_mallocz( p->qstride * a->mb_height);
     avctx->pix_fmt= PIX_FMT_YUV420P;