edb4dadf1fac2292b009e3082770e240345e82cb
[libav.git] / libavcodec / bmpenc.c
1 /*
2 * BMP image format encoder
3 * Copyright (c) 2006, 2007 Michel Bardiaux
4 * Copyright (c) 2009 Daniel Verkamp <daniel at drv.nu>
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23 #include "avcodec.h"
24 #include "bytestream.h"
25 #include "bmp.h"
26
27 static const uint32_t monoblack_pal[] = { 0x000000, 0xFFFFFF };
28 static const uint32_t rgb565_masks[] = { 0xF800, 0x07E0, 0x001F };
29
30 static av_cold int bmp_encode_init(AVCodecContext *avctx){
31 BMPContext *s = avctx->priv_data;
32
33 avcodec_get_frame_defaults((AVFrame*)&s->picture);
34 avctx->coded_frame = (AVFrame*)&s->picture;
35
36 return 0;
37 }
38
39 static int bmp_encode_frame(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){
40 BMPContext *s = avctx->priv_data;
41 AVFrame *pict = data;
42 AVFrame * const p= (AVFrame*)&s->picture;
43 int n_bytes_image, n_bytes_per_row, n_bytes, i, n, hsize;
44 const uint32_t *pal = NULL;
45 int pad_bytes_per_row, bit_count, pal_entries = 0, compression = BMP_RGB;
46 uint8_t *ptr;
47 unsigned char* buf0 = buf;
48 *p = *pict;
49 p->pict_type= FF_I_TYPE;
50 p->key_frame= 1;
51 switch (avctx->pix_fmt) {
52 case PIX_FMT_BGR24:
53 bit_count = 24;
54 break;
55 case PIX_FMT_RGB555:
56 bit_count = 16;
57 break;
58 case PIX_FMT_RGB565:
59 bit_count = 16;
60 compression = BMP_BITFIELDS;
61 pal = rgb565_masks; // abuse pal to hold color masks
62 pal_entries = 3;
63 break;
64 case PIX_FMT_RGB8:
65 case PIX_FMT_BGR8:
66 case PIX_FMT_RGB4_BYTE:
67 case PIX_FMT_BGR4_BYTE:
68 case PIX_FMT_GRAY8:
69 case PIX_FMT_PAL8:
70 bit_count = 8;
71 pal = (uint32_t *)p->data[1];
72 break;
73 case PIX_FMT_MONOBLACK:
74 bit_count = 1;
75 pal = monoblack_pal;
76 break;
77 default:
78 return -1;
79 }
80 if (pal && !pal_entries) pal_entries = 1 << bit_count;
81 n_bytes_per_row = ((int64_t)avctx->width * (int64_t)bit_count + 7LL) >> 3LL;
82 pad_bytes_per_row = (4 - n_bytes_per_row) & 3;
83 n_bytes_image = avctx->height * (n_bytes_per_row + pad_bytes_per_row);
84
85 // STRUCTURE.field refer to the MSVC documentation for BITMAPFILEHEADER
86 // and related pages.
87 #define SIZE_BITMAPFILEHEADER 14
88 #define SIZE_BITMAPINFOHEADER 40
89 hsize = SIZE_BITMAPFILEHEADER + SIZE_BITMAPINFOHEADER + (pal_entries << 2);
90 n_bytes = n_bytes_image + hsize;
91 if(n_bytes>buf_size) {
92 av_log(avctx, AV_LOG_ERROR, "buf size too small (need %d, got %d)\n", n_bytes, buf_size);
93 return -1;
94 }
95 bytestream_put_byte(&buf, 'B'); // BITMAPFILEHEADER.bfType
96 bytestream_put_byte(&buf, 'M'); // do.
97 bytestream_put_le32(&buf, n_bytes); // BITMAPFILEHEADER.bfSize
98 bytestream_put_le16(&buf, 0); // BITMAPFILEHEADER.bfReserved1
99 bytestream_put_le16(&buf, 0); // BITMAPFILEHEADER.bfReserved2
100 bytestream_put_le32(&buf, hsize); // BITMAPFILEHEADER.bfOffBits
101 bytestream_put_le32(&buf, SIZE_BITMAPINFOHEADER); // BITMAPINFOHEADER.biSize
102 bytestream_put_le32(&buf, avctx->width); // BITMAPINFOHEADER.biWidth
103 bytestream_put_le32(&buf, avctx->height); // BITMAPINFOHEADER.biHeight
104 bytestream_put_le16(&buf, 1); // BITMAPINFOHEADER.biPlanes
105 bytestream_put_le16(&buf, bit_count); // BITMAPINFOHEADER.biBitCount
106 bytestream_put_le32(&buf, compression); // BITMAPINFOHEADER.biCompression
107 bytestream_put_le32(&buf, n_bytes_image); // BITMAPINFOHEADER.biSizeImage
108 bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biXPelsPerMeter
109 bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biYPelsPerMeter
110 bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biClrUsed
111 bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biClrImportant
112 for (i = 0; i < pal_entries; i++)
113 bytestream_put_le32(&buf, pal[i] & 0xFFFFFF);
114 // BMP files are bottom-to-top so we start from the end...
115 ptr = p->data[0] + (avctx->height - 1) * p->linesize[0];
116 buf = buf0 + hsize;
117 for(i = 0; i < avctx->height; i++) {
118 if (bit_count == 16) {
119 const uint16_t *src = (const uint16_t *) ptr;
120 uint16_t *dst = (uint16_t *) buf;
121 for(n = 0; n < avctx->width; n++)
122 AV_WL16(dst + n, src[n]);
123 } else {
124 memcpy(buf, ptr, n_bytes_per_row);
125 }
126 buf += n_bytes_per_row;
127 memset(buf, 0, pad_bytes_per_row);
128 buf += pad_bytes_per_row;
129 ptr -= p->linesize[0]; // ... and go back
130 }
131 return n_bytes;
132 }
133
134 AVCodec bmp_encoder = {
135 "bmp",
136 CODEC_TYPE_VIDEO,
137 CODEC_ID_BMP,
138 sizeof(BMPContext),
139 bmp_encode_init,
140 bmp_encode_frame,
141 NULL, //encode_end,
142 .pix_fmts = (const enum PixelFormat[]){
143 PIX_FMT_BGR24,
144 PIX_FMT_RGB555, PIX_FMT_RGB565,
145 PIX_FMT_RGB8, PIX_FMT_BGR8, PIX_FMT_RGB4_BYTE, PIX_FMT_BGR4_BYTE, PIX_FMT_GRAY8, PIX_FMT_PAL8,
146 PIX_FMT_MONOBLACK,
147 PIX_FMT_NONE},
148 .long_name = NULL_IF_CONFIG_SMALL("BMP image"),
149 };