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