/
bmpenc.c
187 lines (176 loc) · 7.06 KB
/
bmpenc.c
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
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
/*
* BMP image format encoder
* Copyright (c) 2006, 2007 Michel Bardiaux
* Copyright (c) 2009 Daniel Verkamp <daniel at drv.nu>
*
* 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
*/
#include "libavutil/imgutils.h"
#include "libavutil/avassert.h"
#include "avcodec.h"
#include "bytestream.h"
#include "bmp.h"
#include "internal.h"
static const uint32_t monoblack_pal[] = { 0x000000, 0xFFFFFF };
static const uint32_t rgb565_masks[] = { 0xF800, 0x07E0, 0x001F };
static const uint32_t rgb444_masks[] = { 0x0F00, 0x00F0, 0x000F };
static av_cold int bmp_encode_init(AVCodecContext *avctx){
switch (avctx->pix_fmt) {
case AV_PIX_FMT_BGRA:
avctx->bits_per_coded_sample = 32;
break;
case AV_PIX_FMT_BGR24:
avctx->bits_per_coded_sample = 24;
break;
case AV_PIX_FMT_RGB555:
case AV_PIX_FMT_RGB565:
case AV_PIX_FMT_RGB444:
avctx->bits_per_coded_sample = 16;
break;
case AV_PIX_FMT_RGB8:
case AV_PIX_FMT_BGR8:
case AV_PIX_FMT_RGB4_BYTE:
case AV_PIX_FMT_BGR4_BYTE:
case AV_PIX_FMT_GRAY8:
case AV_PIX_FMT_PAL8:
avctx->bits_per_coded_sample = 8;
break;
case AV_PIX_FMT_MONOBLACK:
avctx->bits_per_coded_sample = 1;
break;
default:
av_log(avctx, AV_LOG_INFO, "unsupported pixel format\n");
return AVERROR(EINVAL);
}
avctx->coded_frame = av_frame_alloc();
if (!avctx->coded_frame)
return AVERROR(ENOMEM);
return 0;
}
static int bmp_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
const AVFrame *pict, int *got_packet)
{
const AVFrame * const p = pict;
int n_bytes_image, n_bytes_per_row, n_bytes, i, n, hsize, ret;
const uint32_t *pal = NULL;
uint32_t palette256[256];
int pad_bytes_per_row, pal_entries = 0, compression = BMP_RGB;
int bit_count = avctx->bits_per_coded_sample;
uint8_t *ptr, *buf;
avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;
avctx->coded_frame->key_frame = 1;
switch (avctx->pix_fmt) {
case AV_PIX_FMT_RGB444:
compression = BMP_BITFIELDS;
pal = rgb444_masks; // abuse pal to hold color masks
pal_entries = 3;
break;
case AV_PIX_FMT_RGB565:
compression = BMP_BITFIELDS;
pal = rgb565_masks; // abuse pal to hold color masks
pal_entries = 3;
break;
case AV_PIX_FMT_RGB8:
case AV_PIX_FMT_BGR8:
case AV_PIX_FMT_RGB4_BYTE:
case AV_PIX_FMT_BGR4_BYTE:
case AV_PIX_FMT_GRAY8:
av_assert1(bit_count == 8);
avpriv_set_systematic_pal2(palette256, avctx->pix_fmt);
pal = palette256;
break;
case AV_PIX_FMT_PAL8:
pal = (uint32_t *)p->data[1];
break;
case AV_PIX_FMT_MONOBLACK:
pal = monoblack_pal;
break;
}
if (pal && !pal_entries) pal_entries = 1 << bit_count;
n_bytes_per_row = ((int64_t)avctx->width * (int64_t)bit_count + 7LL) >> 3LL;
pad_bytes_per_row = (4 - n_bytes_per_row) & 3;
n_bytes_image = avctx->height * (n_bytes_per_row + pad_bytes_per_row);
// STRUCTURE.field refer to the MSVC documentation for BITMAPFILEHEADER
// and related pages.
#define SIZE_BITMAPFILEHEADER 14
#define SIZE_BITMAPINFOHEADER 40
hsize = SIZE_BITMAPFILEHEADER + SIZE_BITMAPINFOHEADER + (pal_entries << 2);
n_bytes = n_bytes_image + hsize;
if ((ret = ff_alloc_packet2(avctx, pkt, n_bytes)) < 0)
return ret;
buf = pkt->data;
bytestream_put_byte(&buf, 'B'); // BITMAPFILEHEADER.bfType
bytestream_put_byte(&buf, 'M'); // do.
bytestream_put_le32(&buf, n_bytes); // BITMAPFILEHEADER.bfSize
bytestream_put_le16(&buf, 0); // BITMAPFILEHEADER.bfReserved1
bytestream_put_le16(&buf, 0); // BITMAPFILEHEADER.bfReserved2
bytestream_put_le32(&buf, hsize); // BITMAPFILEHEADER.bfOffBits
bytestream_put_le32(&buf, SIZE_BITMAPINFOHEADER); // BITMAPINFOHEADER.biSize
bytestream_put_le32(&buf, avctx->width); // BITMAPINFOHEADER.biWidth
bytestream_put_le32(&buf, avctx->height); // BITMAPINFOHEADER.biHeight
bytestream_put_le16(&buf, 1); // BITMAPINFOHEADER.biPlanes
bytestream_put_le16(&buf, bit_count); // BITMAPINFOHEADER.biBitCount
bytestream_put_le32(&buf, compression); // BITMAPINFOHEADER.biCompression
bytestream_put_le32(&buf, n_bytes_image); // BITMAPINFOHEADER.biSizeImage
bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biXPelsPerMeter
bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biYPelsPerMeter
bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biClrUsed
bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biClrImportant
for (i = 0; i < pal_entries; i++)
bytestream_put_le32(&buf, pal[i] & 0xFFFFFF);
// BMP files are bottom-to-top so we start from the end...
ptr = p->data[0] + (avctx->height - 1) * p->linesize[0];
buf = pkt->data + hsize;
for(i = 0; i < avctx->height; i++) {
if (bit_count == 16) {
const uint16_t *src = (const uint16_t *) ptr;
uint16_t *dst = (uint16_t *) buf;
for(n = 0; n < avctx->width; n++)
AV_WL16(dst + n, src[n]);
} else {
memcpy(buf, ptr, n_bytes_per_row);
}
buf += n_bytes_per_row;
memset(buf, 0, pad_bytes_per_row);
buf += pad_bytes_per_row;
ptr -= p->linesize[0]; // ... and go back
}
pkt->flags |= AV_PKT_FLAG_KEY;
*got_packet = 1;
return 0;
}
static av_cold int bmp_encode_close(AVCodecContext *avctx)
{
av_frame_free(&avctx->coded_frame);
return 0;
}
AVCodec ff_bmp_encoder = {
.name = "bmp",
.long_name = NULL_IF_CONFIG_SMALL("BMP (Windows and OS/2 bitmap)"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_BMP,
.init = bmp_encode_init,
.encode2 = bmp_encode_frame,
.close = bmp_encode_close,
.pix_fmts = (const enum AVPixelFormat[]){
AV_PIX_FMT_BGRA, AV_PIX_FMT_BGR24,
AV_PIX_FMT_RGB565, AV_PIX_FMT_RGB555, AV_PIX_FMT_RGB444,
AV_PIX_FMT_RGB8, AV_PIX_FMT_BGR8, AV_PIX_FMT_RGB4_BYTE, AV_PIX_FMT_BGR4_BYTE, AV_PIX_FMT_GRAY8, AV_PIX_FMT_PAL8,
AV_PIX_FMT_MONOBLACK,
AV_PIX_FMT_NONE
},
};