Merge commit 'b53d8c3ccfeff77874f5ca7c68136b6d87a0a69c'

* commit 'b53d8c3ccfeff77874f5ca7c68136b6d87a0a69c':
  mjpegdec: Drop disabled code

The last chunk is replaced with a comment describing the structure.

Merged-by: Clément Bœsch <u@pkh.me>

diff --cc libavcodec/mjpegdec.c
index 4e78e1e3ae2d8ef174b1e6c501c25d9929ea041e,c670f357c9e0d3efd225b6cbf7312c596cae6b48..8bf2fdfcc14583b8e453a4fb3300e4024d0dcba1
--- 1/libavcodec/mjpegdec.c
--- 2/libavcodec/mjpegdec.c
+++ b/libavcodec/mjpegdec.c
@@@ -1662,24 -1209,17 +1662,16 @@@ static int mjpeg_decode_app(MJpegDecode
              4bytes      field_size
              4bytes      field_size_less_padding
          */
 -        s->buggy_avid = 1;
 -        i = get_bits(&s->gb, 8);
 -        if (i == 2)
 -            s->bottom_field = 1;
 -        else if (i == 1)
 -            s->bottom_field = 0;
 +            s->buggy_avid = 1;
 +        i = get_bits(&s->gb, 8); len--;
 +        av_log(s->avctx, AV_LOG_DEBUG, "polarity %d\n", i);
- #if 0
-         skip_bits(&s->gb, 8);
-         skip_bits(&s->gb, 32);
-         skip_bits(&s->gb, 32);
-         len -= 10;
- #endif
          goto out;
      }
  
- //    len -= 2;
- 
 -    if (id == AV_RL32("JFIF")) {
 +    if (id == AV_RB32("JFIF")) {
          int t_w, t_h, v1, v2;
 +        if (len < 8)
 +            goto out;
          skip_bits(&s->gb, 8); /* the trailing zero-byte */
          v1 = get_bits(&s->gb, 8);
          v2 = get_bits(&s->gb, 8);
@@@ -1856,19 -1285,10 +1848,19 @@@
      /* Apple MJPEG-A */
      if ((s->start_code == APP1) && (len > (0x28 - 8))) {
          id   = get_bits_long(&s->gb, 32);
 -        id   = av_be2ne32(id);
          len -= 4;
          /* Apple MJPEG-A */
 -        if (id == AV_RL32("mjpg")) {
 +        if (id == AV_RB32("mjpg")) {
- #if 0
-             skip_bits(&s->gb, 32); /* field size */
-             skip_bits(&s->gb, 32); /* pad field size */
-             skip_bits(&s->gb, 32); /* next off */
-             skip_bits(&s->gb, 32); /* quant off */
-             skip_bits(&s->gb, 32); /* huff off */
-             skip_bits(&s->gb, 32); /* image off */
-             skip_bits(&s->gb, 32); /* scan off */
-             skip_bits(&s->gb, 32); /* data off */
- #endif
++            /* structure:
++                4bytes      field size
++                4bytes      pad field size
++                4bytes      next off
++                4bytes      quant off
++                4bytes      huff off
++                4bytes      image off
++                4bytes      scan off
++                4bytes      data off
++            */
              if (s->avctx->debug & FF_DEBUG_PICT_INFO)
                  av_log(s->avctx, AV_LOG_INFO, "mjpeg: Apple MJPEG-A header found\n");
          }