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/*
* BMP image format encoder
* Copyright (c) 2006, 2007 Michel Bardiaux
* Copyright (c) 2009 Daniel Verkamp <daniel at drv.nu>
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/imgutils.h"
#include "avcodec.h"
#include "bytestream.h"
#include "bmp.h"
static const uint32_t monoblack_pal[] = { 0x000000, 0xFFFFFF };
static const uint32_t rgb565_masks[] = { 0xF800, 0x07E0, 0x001F };
static av_cold int bmp_encode_init(AVCodecContext *avctx){
BMPContext *s = avctx->priv_data;
avcodec_get_frame_defaults((AVFrame*)&s->picture);
avctx->coded_frame = (AVFrame*)&s->picture;
switch (avctx->pix_fmt) {
case PIX_FMT_BGR24:
avctx->bits_per_coded_sample = 24;
break;
case PIX_FMT_RGB555:
avctx->bits_per_coded_sample = 16;
break;
case PIX_FMT_RGB565:
avctx->bits_per_coded_sample = 16;
break;
case PIX_FMT_RGB8:
case PIX_FMT_BGR8:
case PIX_FMT_RGB4_BYTE:
case PIX_FMT_BGR4_BYTE:
case PIX_FMT_GRAY8:
case PIX_FMT_PAL8:
avctx->bits_per_coded_sample = 8;
break;
case PIX_FMT_MONOBLACK:
avctx->bits_per_coded_sample = 1;
break;
default:
av_log(avctx, AV_LOG_INFO, "unsupported pixel format\n");
return -1;
}
return 0;
}
static int bmp_encode_frame(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){
BMPContext *s = avctx->priv_data;
AVFrame *pict = data;
AVFrame * const p= (AVFrame*)&s->picture;
int n_bytes_image, n_bytes_per_row, n_bytes, i, n, hsize;
const uint32_t *pal = NULL;
int pad_bytes_per_row, pal_entries = 0, compression = BMP_RGB;
int bit_count = avctx->bits_per_coded_sample;
uint8_t *ptr;
unsigned char* buf0 = buf;
*p = *pict;
p->pict_type= FF_I_TYPE;
p->key_frame= 1;
switch (avctx->pix_fmt) {
case PIX_FMT_RGB565:
compression = BMP_BITFIELDS;
pal = rgb565_masks; // abuse pal to hold color masks
pal_entries = 3;
break;
case PIX_FMT_RGB8:
case PIX_FMT_BGR8:
case PIX_FMT_RGB4_BYTE:
case PIX_FMT_BGR4_BYTE:
case PIX_FMT_GRAY8:
ff_set_systematic_pal2((uint32_t*)p->data[1], avctx->pix_fmt);
case PIX_FMT_PAL8:
pal = (uint32_t *)p->data[1];
break;
case 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(n_bytes>buf_size) {
av_log(avctx, AV_LOG_ERROR, "buf size too small (need %d, got %d)\n", n_bytes, buf_size);
return -1;
}
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 = buf0 + 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
}
return n_bytes;
}
AVCodec ff_bmp_encoder = {
"bmp",
AVMEDIA_TYPE_VIDEO,
CODEC_ID_BMP,
sizeof(BMPContext),
bmp_encode_init,
bmp_encode_frame,
NULL, //encode_end,
.pix_fmts = (const enum PixelFormat[]){
PIX_FMT_BGR24,
PIX_FMT_RGB555, PIX_FMT_RGB565,
PIX_FMT_RGB8, PIX_FMT_BGR8, PIX_FMT_RGB4_BYTE, PIX_FMT_BGR4_BYTE, PIX_FMT_GRAY8, PIX_FMT_PAL8,
PIX_FMT_MONOBLACK,
PIX_FMT_NONE},
.long_name = NULL_IF_CONFIG_SMALL("BMP image"),
};
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