FFmpeg: libavcodec/sunrastenc.c Source File

FFmpeg
sunrastenc.c
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1 /*
2  * Sun Rasterfile (.sun/.ras/im{1,8,24}/.sunras) image encoder
3  * Copyright (c) 2012 Aneesh Dogra (lionaneesh) <lionaneesh@gmail.com>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "avcodec.h"
23 #include "bytestream.h"
24 #include "internal.h"
25 #include "sunrast.h"
26 
27  typedef struct SUNRASTContext {
28   PutByteContext p;
29   int depth; ///< depth of pixel
30   int length; ///< length (bytes) of image
31   int type; ///< type of file
32   int maptype; ///< type of colormap
33   int maplength; ///< length (bytes) of colormap
34   int size;
35 } SUNRASTContext;
36 
37  static void sunrast_image_write_header(AVCodecContext *avctx)
38 {
39  SUNRASTContext *s = avctx->priv_data;
40 
41  bytestream2_put_be32u(&s->p, RAS_MAGIC);
42  bytestream2_put_be32u(&s->p, avctx->width);
43  bytestream2_put_be32u(&s->p, avctx->height);
44  bytestream2_put_be32u(&s->p, s->depth);
45  bytestream2_put_be32u(&s->p, s->length);
46  bytestream2_put_be32u(&s->p, s->type);
47  bytestream2_put_be32u(&s->p, s->maptype);
48  bytestream2_put_be32u(&s->p, s->maplength);
49 }
50 
51  static void sunrast_image_write_image(AVCodecContext *avctx,
52  const uint8_t *pixels,
53  const uint32_t *palette_data,
54  int linesize)
55 {
56  SUNRASTContext *s = avctx->priv_data;
57  const uint8_t *ptr;
58  int len, alen, x, y;
59 
60  if (s->maplength) { // palettized
61  PutByteContext pb_r, pb_g;
62  int len = s->maplength / 3;
63 
64  pb_r = s->p;
65  bytestream2_skip_p(&s->p, len);
66  pb_g = s->p;
67  bytestream2_skip_p(&s->p, len);
68 
69  for (x = 0; x < len; x++) {
70  uint32_t pixel = palette_data[x];
71 
72  bytestream2_put_byteu(&pb_r, (pixel >> 16) & 0xFF);
73  bytestream2_put_byteu(&pb_g, (pixel >> 8) & 0xFF);
74  bytestream2_put_byteu(&s->p, pixel & 0xFF);
75  }
76  }
77 
78  len = (s->depth * avctx->width + 7) >> 3;
79  alen = len + (len & 1);
80  ptr = pixels;
81 
82  if (s->type == RT_BYTE_ENCODED) {
83  uint8_t value, value2;
84  int run;
85 
86  ptr = pixels;
87 
88 #define GET_VALUE y >= avctx->height ? 0 : x >= len ? ptr[len-1] : ptr[x]
89 
90  x = 0, y = 0;
91  value2 = GET_VALUE;
92  while (y < avctx->height) {
93  run = 1;
94  value = value2;
95  x++;
96  if (x >= alen) {
97  x = 0;
98  ptr += linesize, y++;
99  }
100 
101  value2 = GET_VALUE;
102  while (value2 == value && run < 256 && y < avctx->height) {
103  x++;
104  run++;
105  if (x >= alen) {
106  x = 0;
107  ptr += linesize, y++;
108  }
109  value2 = GET_VALUE;
110  }
111 
112  if (run > 2 || value == RLE_TRIGGER) {
113  bytestream2_put_byteu(&s->p, RLE_TRIGGER);
114  bytestream2_put_byteu(&s->p, run - 1);
115  if (run > 1)
116  bytestream2_put_byteu(&s->p, value);
117  } else if (run == 1) {
118  bytestream2_put_byteu(&s->p, value);
119  } else
120  bytestream2_put_be16u(&s->p, (value << 8) | value);
121  }
122 
123  // update data length for header
124  s->length = bytestream2_tell_p(&s->p) - 32 - s->maplength;
125  } else {
126  for (y = 0; y < avctx->height; y++) {
127  bytestream2_put_buffer(&s->p, ptr, len);
128  if (len < alen)
129  bytestream2_put_byteu(&s->p, 0);
130  ptr += linesize;
131  }
132  }
133 }
134 
135  static av_cold int sunrast_encode_init(AVCodecContext *avctx)
136 {
137  SUNRASTContext *s = avctx->priv_data;
138 
139  switch (avctx->coder_type) {
140  case FF_CODER_TYPE_RLE:
141  s->type = RT_BYTE_ENCODED;
142  break;
143  case FF_CODER_TYPE_RAW:
144  s->type = RT_STANDARD;
145  break;
146  default:
147  av_log(avctx, AV_LOG_ERROR, "invalid coder_type\n");
148  return AVERROR(EINVAL);
149  }
150 
151  s->maptype = RMT_NONE;
152  s->maplength = 0;
153 
154  switch (avctx->pix_fmt) {
155  case AV_PIX_FMT_MONOWHITE:
156  s->depth = 1;
157  break;
158  case AV_PIX_FMT_PAL8 :
159  s->maptype = RMT_EQUAL_RGB;
160  s->maplength = 3 * 256;
161  case AV_PIX_FMT_GRAY8:
162  s->depth = 8;
163  break;
164  case AV_PIX_FMT_BGR24:
165  s->depth = 24;
166  break;
167  default:
168  return AVERROR_BUG;
169  }
170  s->length = avctx->height * (FFALIGN(avctx->width * s->depth, 16) >> 3);
171  s->size = 32 + s->maplength +
172  s->length * (s->type == RT_BYTE_ENCODED ? 2 : 1);
173 
174  return 0;
175 }
176 
177  static int sunrast_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
178  const AVFrame *frame, int *got_packet_ptr)
179 {
180  SUNRASTContext *s = avctx->priv_data;
181  int ret;
182 
183  if ((ret = ff_alloc_packet2(avctx, avpkt, s->size)) < 0)
184  return ret;
185 
186  bytestream2_init_writer(&s->p, avpkt->data, avpkt->size);
187  sunrast_image_write_header(avctx);
188  sunrast_image_write_image(avctx, frame->data[0],
189  (const uint32_t *)frame->data[1],
190  frame->linesize[0]);
191  // update data length in header after RLE
192  if (s->type == RT_BYTE_ENCODED)
193  AV_WB32(&avpkt->data[16], s->length);
194 
195  *got_packet_ptr = 1;
196  avpkt->flags |= AV_PKT_FLAG_KEY;
197  avpkt->size = bytestream2_tell_p(&s->p);
198  return 0;
199 }
200 
201  static av_cold int sunrast_encode_close(AVCodecContext *avctx)
202 {
203  av_frame_free(&avctx->coded_frame);
204  return 0;
205 }
206 
207  static const AVCodecDefault sunrast_defaults[] = {
208  { "coder", "rle" },
209  { NULL },
210 };
211 
212  AVCodec ff_sunrast_encoder = {
213  .name = "sunrast",
214  .long_name = NULL_IF_CONFIG_SMALL("Sun Rasterfile image"),
215  .type = AVMEDIA_TYPE_VIDEO,
216  .id = AV_CODEC_ID_SUNRAST,
217  .priv_data_size = sizeof(SUNRASTContext),
218  .init = sunrast_encode_init,
219  .close = sunrast_encode_close,
220  .encode2 = sunrast_encode_frame,
221  .defaults = sunrast_defaults,
222  .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24,
223  AV_PIX_FMT_PAL8,
224  AV_PIX_FMT_GRAY8,
225  AV_PIX_FMT_MONOWHITE,
226  AV_PIX_FMT_NONE },
227 };
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