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1 /*
2  * PC Paintbrush PCX (.pcx) image encoder
3  * Copyright (c) 2009 Daniel Verkamp <daniel at drv.nu>
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 /**
23  * @file
24  * PCX image encoder
25  * @author Daniel Verkamp
26  * @see http://bespin.org/~qz/pc-gpe/pcx.txt
27  */
28 
29 #include "avcodec.h"
30 #include "bytestream.h"
31 #include "libavutil/imgutils.h"
32 #include "internal.h"
33 
34 static const uint32_t monoblack_pal[16] = { 0x000000, 0xFFFFFF };
35 
pcx_encode_init(AVCodecContext * avctx)36 static av_cold int pcx_encode_init(AVCodecContext *avctx)
37 {
38 #if FF_API_CODED_FRAME
39 FF_DISABLE_DEPRECATION_WARNINGS
40     avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;
41     avctx->coded_frame->key_frame = 1;
42 FF_ENABLE_DEPRECATION_WARNINGS
43 #endif
44 
45     return 0;
46 }
47 
48 /**
49  * PCX run-length encoder
50  * @param dst output buffer
51  * @param dst_size size of output buffer
52  * @param src input buffer
53  * @param src_plane_size size of one plane of input buffer in bytes
54  * @param nplanes number of planes in input buffer
55  * @return number of bytes written to dst or -1 on error
56  * @bug will not work for nplanes != 1 && bpp != 8
57  */
pcx_rle_encode(uint8_t * dst,int dst_size,const uint8_t * src,int src_plane_size,int nplanes)58 static int pcx_rle_encode(      uint8_t *dst, int dst_size,
59                           const uint8_t *src, int src_plane_size, int nplanes)
60 {
61     int p;
62     const uint8_t *dst_start = dst;
63 
64     // check worst-case upper bound on dst_size
65     if (dst_size < 2LL * src_plane_size * nplanes || src_plane_size <= 0)
66         return AVERROR(EINVAL);
67 
68     for (p = 0; p < nplanes; p++) {
69         int count = 1;
70         const uint8_t *src_plane = src + p;
71         const uint8_t *src_plane_end = src_plane + src_plane_size * nplanes;
72         uint8_t prev = *src_plane;
73         src_plane += nplanes;
74 
75         for (; ; src_plane += nplanes) {
76             if (src_plane < src_plane_end && *src_plane == prev && count < 0x3F) {
77                 // current byte is same as prev
78                 ++count;
79             } else {
80                 // output prev * count
81                 if (count != 1 || prev >= 0xC0)
82                     *dst++ = 0xC0 | count;
83                 *dst++ = prev;
84 
85                 if (src_plane == src_plane_end)
86                     break;
87 
88                 // start new run
89                 count = 1;
90                 prev = *src_plane;
91             }
92         }
93     }
94 
95     return dst - dst_start;
96 }
97 
pcx_encode_frame(AVCodecContext * avctx,AVPacket * pkt,const AVFrame * frame,int * got_packet)98 static int pcx_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
99                             const AVFrame *frame, int *got_packet)
100 {
101     const uint8_t *buf_end;
102     uint8_t *buf;
103 
104     int bpp, nplanes, i, y, line_bytes, written, ret, max_pkt_size, sw, sh;
105     const uint32_t *pal = NULL;
106     uint32_t palette256[256];
107     const uint8_t *src;
108 
109     if (avctx->width > 65535 || avctx->height > 65535) {
110         av_log(avctx, AV_LOG_ERROR, "image dimensions do not fit in 16 bits\n");
111         return AVERROR(EINVAL);
112     }
113 
114     switch (avctx->pix_fmt) {
115     case AV_PIX_FMT_RGB24:
116         bpp = 8;
117         nplanes = 3;
118         break;
119     case AV_PIX_FMT_RGB8:
120     case AV_PIX_FMT_BGR8:
121     case AV_PIX_FMT_RGB4_BYTE:
122     case AV_PIX_FMT_BGR4_BYTE:
123     case AV_PIX_FMT_GRAY8:
124         bpp = 8;
125         nplanes = 1;
126         avpriv_set_systematic_pal2(palette256, avctx->pix_fmt);
127         pal = palette256;
128         break;
129     case AV_PIX_FMT_PAL8:
130         bpp = 8;
131         nplanes = 1;
132         pal = (uint32_t *)frame->data[1];
133         break;
134     case AV_PIX_FMT_MONOBLACK:
135         bpp = 1;
136         nplanes = 1;
137         pal = monoblack_pal;
138         break;
139     default:
140         av_log(avctx, AV_LOG_ERROR, "unsupported pixfmt\n");
141         return AVERROR(EINVAL);
142     }
143 
144     line_bytes = (avctx->width * bpp + 7) >> 3;
145     line_bytes = (line_bytes + 1) & ~1;
146 
147     max_pkt_size = 128 + avctx->height * 2 * line_bytes * nplanes + (pal ? 256*3 + 1 : 0);
148     if ((ret = ff_alloc_packet2(avctx, pkt, max_pkt_size, 0)) < 0)
149         return ret;
150     buf     = pkt->data;
151     buf_end = pkt->data + pkt->size;
152 
153     sw = avctx->sample_aspect_ratio.num;
154     sh = avctx->sample_aspect_ratio.den;
155     if (sw > 0xFFFFu || sh > 0xFFFFu)
156         av_reduce(&sw, &sh, sw, sh, 0xFFFFu);
157 
158     bytestream_put_byte(&buf, 10);                  // manufacturer
159     bytestream_put_byte(&buf, 5);                   // version
160     bytestream_put_byte(&buf, 1);                   // encoding
161     bytestream_put_byte(&buf, bpp);                 // bits per pixel per plane
162     bytestream_put_le16(&buf, 0);                   // x min
163     bytestream_put_le16(&buf, 0);                   // y min
164     bytestream_put_le16(&buf, avctx->width - 1);    // x max
165     bytestream_put_le16(&buf, avctx->height - 1);   // y max
166     bytestream_put_le16(&buf, sw);                  // horizontal DPI
167     bytestream_put_le16(&buf, sh);                  // vertical DPI
168     for (i = 0; i < 16; i++)
169         bytestream_put_be24(&buf, pal ? pal[i] : 0);// palette (<= 16 color only)
170     bytestream_put_byte(&buf, 0);                   // reserved
171     bytestream_put_byte(&buf, nplanes);             // number of planes
172     bytestream_put_le16(&buf, line_bytes);          // scanline plane size in bytes
173 
174     while (buf - pkt->data < 128)
175         *buf++= 0;
176 
177     src = frame->data[0];
178 
179     for (y = 0; y < avctx->height; y++) {
180         if ((written = pcx_rle_encode(buf, buf_end - buf,
181                                       src, line_bytes, nplanes)) < 0) {
182             av_log(avctx, AV_LOG_ERROR, "buffer too small\n");
183             return AVERROR_BUG;
184         }
185         buf += written;
186         src += frame->linesize[0];
187     }
188 
189     if (nplanes == 1 && bpp == 8) {
190         if (buf_end - buf < 257) {
191             av_log(avctx, AV_LOG_ERROR, "buffer too small\n");
192             return AVERROR_BUG;
193         }
194         bytestream_put_byte(&buf, 12);
195         for (i = 0; i < 256; i++) {
196             bytestream_put_be24(&buf, pal[i]);
197         }
198     }
199 
200     pkt->size   = buf - pkt->data;
201     pkt->flags |= AV_PKT_FLAG_KEY;
202     *got_packet = 1;
203 
204     return 0;
205 }
206 
207 AVCodec ff_pcx_encoder = {
208     .name           = "pcx",
209     .long_name      = NULL_IF_CONFIG_SMALL("PC Paintbrush PCX image"),
210     .type           = AVMEDIA_TYPE_VIDEO,
211     .id             = AV_CODEC_ID_PCX,
212     .init           = pcx_encode_init,
213     .encode2        = pcx_encode_frame,
214     .pix_fmts       = (const enum AVPixelFormat[]){
215         AV_PIX_FMT_RGB24,
216         AV_PIX_FMT_RGB8, AV_PIX_FMT_BGR8, AV_PIX_FMT_RGB4_BYTE, AV_PIX_FMT_BGR4_BYTE,
217         AV_PIX_FMT_GRAY8, AV_PIX_FMT_PAL8,
218         AV_PIX_FMT_MONOBLACK,
219         AV_PIX_FMT_NONE
220     },
221 };
222