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 Libav. 7 * 8 * Libav 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 * Libav 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 Libav; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 21 */ 22 23#include "libavutil/imgutils.h" 24#include "avcodec.h" 25#include "bytestream.h" 26#include "bmp.h" 27 28static const uint32_t monoblack_pal[] = { 0x000000, 0xFFFFFF }; 29static const uint32_t rgb565_masks[] = { 0xF800, 0x07E0, 0x001F }; 30static const uint32_t rgb444_masks[] = { 0x0F00, 0x00F0, 0x000F }; 31 32static av_cold int bmp_encode_init(AVCodecContext *avctx){ 33 BMPContext *s = avctx->priv_data; 34 35 avcodec_get_frame_defaults((AVFrame*)&s->picture); 36 avctx->coded_frame = (AVFrame*)&s->picture; 37 38 switch (avctx->pix_fmt) { 39 case PIX_FMT_BGR24: 40 avctx->bits_per_coded_sample = 24; 41 break; 42 case PIX_FMT_RGB555: 43 case PIX_FMT_RGB565: 44 case PIX_FMT_RGB444: 45 avctx->bits_per_coded_sample = 16; 46 break; 47 case PIX_FMT_RGB8: 48 case PIX_FMT_BGR8: 49 case PIX_FMT_RGB4_BYTE: 50 case PIX_FMT_BGR4_BYTE: 51 case PIX_FMT_GRAY8: 52 case PIX_FMT_PAL8: 53 avctx->bits_per_coded_sample = 8; 54 break; 55 case PIX_FMT_MONOBLACK: 56 avctx->bits_per_coded_sample = 1; 57 break; 58 default: 59 av_log(avctx, AV_LOG_INFO, "unsupported pixel format\n"); 60 return -1; 61 } 62 63 return 0; 64} 65 66static int bmp_encode_frame(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){ 67 BMPContext *s = avctx->priv_data; 68 AVFrame *pict = data; 69 AVFrame * const p= (AVFrame*)&s->picture; 70 int n_bytes_image, n_bytes_per_row, n_bytes, i, n, hsize; 71 const uint32_t *pal = NULL; 72 int pad_bytes_per_row, pal_entries = 0, compression = BMP_RGB; 73 int bit_count = avctx->bits_per_coded_sample; 74 uint8_t *ptr; 75 unsigned char* buf0 = buf; 76 *p = *pict; 77 p->pict_type= AV_PICTURE_TYPE_I; 78 p->key_frame= 1; 79 switch (avctx->pix_fmt) { 80 case PIX_FMT_RGB444: 81 compression = BMP_BITFIELDS; 82 pal = rgb444_masks; // abuse pal to hold color masks 83 pal_entries = 3; 84 break; 85 case PIX_FMT_RGB565: 86 compression = BMP_BITFIELDS; 87 pal = rgb565_masks; // abuse pal to hold color masks 88 pal_entries = 3; 89 break; 90 case PIX_FMT_RGB8: 91 case PIX_FMT_BGR8: 92 case PIX_FMT_RGB4_BYTE: 93 case PIX_FMT_BGR4_BYTE: 94 case PIX_FMT_GRAY8: 95 ff_set_systematic_pal2((uint32_t*)p->data[1], avctx->pix_fmt); 96 case PIX_FMT_PAL8: 97 pal = (uint32_t *)p->data[1]; 98 break; 99 case PIX_FMT_MONOBLACK: 100 pal = monoblack_pal; 101 break; 102 } 103 if (pal && !pal_entries) pal_entries = 1 << bit_count; 104 n_bytes_per_row = ((int64_t)avctx->width * (int64_t)bit_count + 7LL) >> 3LL; 105 pad_bytes_per_row = (4 - n_bytes_per_row) & 3; 106 n_bytes_image = avctx->height * (n_bytes_per_row + pad_bytes_per_row); 107 108 // STRUCTURE.field refer to the MSVC documentation for BITMAPFILEHEADER 109 // and related pages. 110#define SIZE_BITMAPFILEHEADER 14 111#define SIZE_BITMAPINFOHEADER 40 112 hsize = SIZE_BITMAPFILEHEADER + SIZE_BITMAPINFOHEADER + (pal_entries << 2); 113 n_bytes = n_bytes_image + hsize; 114 if(n_bytes>buf_size) { 115 av_log(avctx, AV_LOG_ERROR, "buf size too small (need %d, got %d)\n", n_bytes, buf_size); 116 return -1; 117 } 118 bytestream_put_byte(&buf, 'B'); // BITMAPFILEHEADER.bfType 119 bytestream_put_byte(&buf, 'M'); // do. 120 bytestream_put_le32(&buf, n_bytes); // BITMAPFILEHEADER.bfSize 121 bytestream_put_le16(&buf, 0); // BITMAPFILEHEADER.bfReserved1 122 bytestream_put_le16(&buf, 0); // BITMAPFILEHEADER.bfReserved2 123 bytestream_put_le32(&buf, hsize); // BITMAPFILEHEADER.bfOffBits 124 bytestream_put_le32(&buf, SIZE_BITMAPINFOHEADER); // BITMAPINFOHEADER.biSize 125 bytestream_put_le32(&buf, avctx->width); // BITMAPINFOHEADER.biWidth 126 bytestream_put_le32(&buf, avctx->height); // BITMAPINFOHEADER.biHeight 127 bytestream_put_le16(&buf, 1); // BITMAPINFOHEADER.biPlanes 128 bytestream_put_le16(&buf, bit_count); // BITMAPINFOHEADER.biBitCount 129 bytestream_put_le32(&buf, compression); // BITMAPINFOHEADER.biCompression 130 bytestream_put_le32(&buf, n_bytes_image); // BITMAPINFOHEADER.biSizeImage 131 bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biXPelsPerMeter 132 bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biYPelsPerMeter 133 bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biClrUsed 134 bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biClrImportant 135 for (i = 0; i < pal_entries; i++) 136 bytestream_put_le32(&buf, pal[i] & 0xFFFFFF); 137 // BMP files are bottom-to-top so we start from the end... 138 ptr = p->data[0] + (avctx->height - 1) * p->linesize[0]; 139 buf = buf0 + hsize; 140 for(i = 0; i < avctx->height; i++) { 141 if (bit_count == 16) { 142 const uint16_t *src = (const uint16_t *) ptr; 143 uint16_t *dst = (uint16_t *) buf; 144 for(n = 0; n < avctx->width; n++) 145 AV_WL16(dst + n, src[n]); 146 } else { 147 memcpy(buf, ptr, n_bytes_per_row); 148 } 149 buf += n_bytes_per_row; 150 memset(buf, 0, pad_bytes_per_row); 151 buf += pad_bytes_per_row; 152 ptr -= p->linesize[0]; // ... and go back 153 } 154 return n_bytes; 155} 156 157AVCodec ff_bmp_encoder = { 158 .name = "bmp", 159 .type = AVMEDIA_TYPE_VIDEO, 160 .id = CODEC_ID_BMP, 161 .priv_data_size = sizeof(BMPContext), 162 .init = bmp_encode_init, 163 .encode = bmp_encode_frame, 164 .pix_fmts = (const enum PixelFormat[]){ 165 PIX_FMT_BGR24, 166 PIX_FMT_RGB555, PIX_FMT_RGB444, PIX_FMT_RGB565, 167 PIX_FMT_RGB8, PIX_FMT_BGR8, PIX_FMT_RGB4_BYTE, PIX_FMT_BGR4_BYTE, PIX_FMT_GRAY8, PIX_FMT_PAL8, 168 PIX_FMT_MONOBLACK, 169 PIX_FMT_NONE}, 170 .long_name = NULL_IF_CONFIG_SMALL("BMP image"), 171}; 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