Blame view

ffmpeg-4.2.2/libavcodec/cljrenc.c 4.18 KB
aac5773f   hucm   功能基本完成,接口待打磨
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
  /*
   * Cirrus Logic AccuPak (CLJR) encoder
   * Copyright (c) 2003 Alex Beregszaszi
   *
   * This file is part of FFmpeg.
   *
   * FFmpeg is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * FFmpeg is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with FFmpeg; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
   */
  
  /**
   * @file
   * Cirrus Logic AccuPak encoder.
   */
  
  #include "libavutil/common.h"
  #include "libavutil/opt.h"
  
  #include "avcodec.h"
  #include "internal.h"
  #include "put_bits.h"
  
  typedef struct CLJRContext {
      AVClass        *avclass;
      int             dither_type;
  } CLJRContext;
  
  static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
                          const AVFrame *p, int *got_packet)
  {
      CLJRContext *a = avctx->priv_data;
      PutBitContext pb;
      int x, y, ret;
      uint32_t dither= avctx->frame_number;
      static const uint32_t ordered_dither[2][2] =
      {
          { 0x10400000, 0x104F0000 },
          { 0xCB2A0000, 0xCB250000 },
      };
  
      if (avctx->width%4 && avctx->strict_std_compliance > FF_COMPLIANCE_UNOFFICIAL) {
           av_log(avctx, AV_LOG_ERROR,
                  "Widths which are not a multiple of 4 might fail with some decoders, "
                  "use vstrict=-1 / -strict -1 to use %d anyway.\n", avctx->width);
           return AVERROR_EXPERIMENTAL;
      }
  
      if ((ret = ff_alloc_packet2(avctx, pkt, 32*avctx->height*avctx->width/4, 0)) < 0)
          return ret;
  
      init_put_bits(&pb, pkt->data, pkt->size);
  
      for (y = 0; y < avctx->height; y++) {
          uint8_t *luma = &p->data[0][y * p->linesize[0]];
          uint8_t *cb   = &p->data[1][y * p->linesize[1]];
          uint8_t *cr   = &p->data[2][y * p->linesize[2]];
          uint8_t luma_tmp[4];
          for (x = 0; x < avctx->width; x += 4) {
              switch (a->dither_type) {
              case 0: dither = 0x492A0000;                       break;
              case 1: dither = dither * 1664525 + 1013904223;    break;
              case 2: dither = ordered_dither[ y&1 ][ (x>>2)&1 ];break;
              }
              if (x+3 >= avctx->width) {
                  memset(luma_tmp, 0, sizeof(luma_tmp));
                  memcpy(luma_tmp, luma, avctx->width - x);
                  luma = luma_tmp;
              }
              put_bits(&pb, 5, (249*(luma[3] +  (dither>>29)   )) >> 11);
              put_bits(&pb, 5, (249*(luma[2] + ((dither>>26)&7))) >> 11);
              put_bits(&pb, 5, (249*(luma[1] + ((dither>>23)&7))) >> 11);
              put_bits(&pb, 5, (249*(luma[0] + ((dither>>20)&7))) >> 11);
              luma += 4;
              put_bits(&pb, 6, (253*(*(cb++) + ((dither>>18)&3))) >> 10);
              put_bits(&pb, 6, (253*(*(cr++) + ((dither>>16)&3))) >> 10);
          }
      }
  
      flush_put_bits(&pb);
  
      pkt->size   = put_bits_count(&pb) / 8;
      pkt->flags |= AV_PKT_FLAG_KEY;
      *got_packet = 1;
      return 0;
  }
  
  #define OFFSET(x) offsetof(CLJRContext, x)
  #define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
  static const AVOption options[] = {
      { "dither_type",   "Dither type",   OFFSET(dither_type),        AV_OPT_TYPE_INT, { .i64=1 }, 0, 2, VE},
      { NULL },
  };
  
  static const AVClass cljr_class = {
      .class_name = "cljr encoder",
      .item_name  = av_default_item_name,
      .option     = options,
      .version    = LIBAVUTIL_VERSION_INT,
  };
  
  AVCodec ff_cljr_encoder = {
      .name           = "cljr",
      .long_name      = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
      .type           = AVMEDIA_TYPE_VIDEO,
      .id             = AV_CODEC_ID_CLJR,
      .priv_data_size = sizeof(CLJRContext),
      .encode2        = encode_frame,
      .pix_fmts       = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV411P,
                                                     AV_PIX_FMT_NONE },
      .priv_class     = &cljr_class,
  };