Libav
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00001 /* 00002 * BMP image format encoder 00003 * Copyright (c) 2006, 2007 Michel Bardiaux 00004 * Copyright (c) 2009 Daniel Verkamp <daniel at drv.nu> 00005 * 00006 * This file is part of FFmpeg. 00007 * 00008 * FFmpeg is free software; you can redistribute it and/or 00009 * modify it under the terms of the GNU Lesser General Public 00010 * License as published by the Free Software Foundation; either 00011 * version 2.1 of the License, or (at your option) any later version. 00012 * 00013 * FFmpeg is distributed in the hope that it will be useful, 00014 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00015 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00016 * Lesser General Public License for more details. 00017 * 00018 * You should have received a copy of the GNU Lesser General Public 00019 * License along with FFmpeg; if not, write to the Free Software 00020 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00021 */ 00022 00023 #include "avcodec.h" 00024 #include "bytestream.h" 00025 #include "bmp.h" 00026 00027 static const uint32_t monoblack_pal[] = { 0x000000, 0xFFFFFF }; 00028 static const uint32_t rgb565_masks[] = { 0xF800, 0x07E0, 0x001F }; 00029 00030 static av_cold int bmp_encode_init(AVCodecContext *avctx){ 00031 BMPContext *s = avctx->priv_data; 00032 00033 avcodec_get_frame_defaults((AVFrame*)&s->picture); 00034 avctx->coded_frame = (AVFrame*)&s->picture; 00035 00036 return 0; 00037 } 00038 00039 static int bmp_encode_frame(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){ 00040 BMPContext *s = avctx->priv_data; 00041 AVFrame *pict = data; 00042 AVFrame * const p= (AVFrame*)&s->picture; 00043 int n_bytes_image, n_bytes_per_row, n_bytes, i, n, hsize; 00044 const uint32_t *pal = NULL; 00045 int pad_bytes_per_row, bit_count, pal_entries = 0, compression = BMP_RGB; 00046 uint8_t *ptr; 00047 unsigned char* buf0 = buf; 00048 *p = *pict; 00049 p->pict_type= FF_I_TYPE; 00050 p->key_frame= 1; 00051 switch (avctx->pix_fmt) { 00052 case PIX_FMT_BGR24: 00053 bit_count = 24; 00054 break; 00055 case PIX_FMT_RGB555: 00056 bit_count = 16; 00057 break; 00058 case PIX_FMT_RGB565: 00059 bit_count = 16; 00060 compression = BMP_BITFIELDS; 00061 pal = rgb565_masks; // abuse pal to hold color masks 00062 pal_entries = 3; 00063 break; 00064 case PIX_FMT_RGB8: 00065 case PIX_FMT_BGR8: 00066 case PIX_FMT_RGB4_BYTE: 00067 case PIX_FMT_BGR4_BYTE: 00068 case PIX_FMT_GRAY8: 00069 case PIX_FMT_PAL8: 00070 bit_count = 8; 00071 pal = (uint32_t *)p->data[1]; 00072 break; 00073 case PIX_FMT_MONOBLACK: 00074 bit_count = 1; 00075 pal = monoblack_pal; 00076 break; 00077 default: 00078 return -1; 00079 } 00080 if (pal && !pal_entries) pal_entries = 1 << bit_count; 00081 n_bytes_per_row = ((int64_t)avctx->width * (int64_t)bit_count + 7LL) >> 3LL; 00082 pad_bytes_per_row = (4 - n_bytes_per_row) & 3; 00083 n_bytes_image = avctx->height * (n_bytes_per_row + pad_bytes_per_row); 00084 00085 // STRUCTURE.field refer to the MSVC documentation for BITMAPFILEHEADER 00086 // and related pages. 00087 #define SIZE_BITMAPFILEHEADER 14 00088 #define SIZE_BITMAPINFOHEADER 40 00089 hsize = SIZE_BITMAPFILEHEADER + SIZE_BITMAPINFOHEADER + (pal_entries << 2); 00090 n_bytes = n_bytes_image + hsize; 00091 if(n_bytes>buf_size) { 00092 av_log(avctx, AV_LOG_ERROR, "buf size too small (need %d, got %d)\n", n_bytes, buf_size); 00093 return -1; 00094 } 00095 bytestream_put_byte(&buf, 'B'); // BITMAPFILEHEADER.bfType 00096 bytestream_put_byte(&buf, 'M'); // do. 00097 bytestream_put_le32(&buf, n_bytes); // BITMAPFILEHEADER.bfSize 00098 bytestream_put_le16(&buf, 0); // BITMAPFILEHEADER.bfReserved1 00099 bytestream_put_le16(&buf, 0); // BITMAPFILEHEADER.bfReserved2 00100 bytestream_put_le32(&buf, hsize); // BITMAPFILEHEADER.bfOffBits 00101 bytestream_put_le32(&buf, SIZE_BITMAPINFOHEADER); // BITMAPINFOHEADER.biSize 00102 bytestream_put_le32(&buf, avctx->width); // BITMAPINFOHEADER.biWidth 00103 bytestream_put_le32(&buf, avctx->height); // BITMAPINFOHEADER.biHeight 00104 bytestream_put_le16(&buf, 1); // BITMAPINFOHEADER.biPlanes 00105 bytestream_put_le16(&buf, bit_count); // BITMAPINFOHEADER.biBitCount 00106 bytestream_put_le32(&buf, compression); // BITMAPINFOHEADER.biCompression 00107 bytestream_put_le32(&buf, n_bytes_image); // BITMAPINFOHEADER.biSizeImage 00108 bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biXPelsPerMeter 00109 bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biYPelsPerMeter 00110 bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biClrUsed 00111 bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biClrImportant 00112 for (i = 0; i < pal_entries; i++) 00113 bytestream_put_le32(&buf, pal[i] & 0xFFFFFF); 00114 // BMP files are bottom-to-top so we start from the end... 00115 ptr = p->data[0] + (avctx->height - 1) * p->linesize[0]; 00116 buf = buf0 + hsize; 00117 for(i = 0; i < avctx->height; i++) { 00118 if (bit_count == 16) { 00119 const uint16_t *src = (const uint16_t *) ptr; 00120 uint16_t *dst = (uint16_t *) buf; 00121 for(n = 0; n < avctx->width; n++) 00122 AV_WL16(dst + n, src[n]); 00123 } else { 00124 memcpy(buf, ptr, n_bytes_per_row); 00125 } 00126 buf += n_bytes_per_row; 00127 memset(buf, 0, pad_bytes_per_row); 00128 buf += pad_bytes_per_row; 00129 ptr -= p->linesize[0]; // ... and go back 00130 } 00131 return n_bytes; 00132 } 00133 00134 AVCodec bmp_encoder = { 00135 "bmp", 00136 AVMEDIA_TYPE_VIDEO, 00137 CODEC_ID_BMP, 00138 sizeof(BMPContext), 00139 bmp_encode_init, 00140 bmp_encode_frame, 00141 NULL, //encode_end, 00142 .pix_fmts = (const enum PixelFormat[]){ 00143 PIX_FMT_BGR24, 00144 PIX_FMT_RGB555, PIX_FMT_RGB565, 00145 PIX_FMT_RGB8, PIX_FMT_BGR8, PIX_FMT_RGB4_BYTE, PIX_FMT_BGR4_BYTE, PIX_FMT_GRAY8, PIX_FMT_PAL8, 00146 PIX_FMT_MONOBLACK, 00147 PIX_FMT_NONE}, 00148 .long_name = NULL_IF_CONFIG_SMALL("BMP image"), 00149 };