FFmpeg
bmpenc.c
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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 "config.h"
24 
25 #include "libavutil/imgutils.h"
26 #include "libavutil/avassert.h"
27 #include "avcodec.h"
28 #include "bytestream.h"
29 #include "bmp.h"
30 #include "encode.h"
31 #include "internal.h"
32 
33 static const uint32_t monoblack_pal[] = { 0x000000, 0xFFFFFF };
34 static const uint32_t rgb565_masks[] = { 0xF800, 0x07E0, 0x001F };
35 static const uint32_t rgb444_masks[] = { 0x0F00, 0x00F0, 0x000F };
36 
38  switch (avctx->pix_fmt) {
39  case AV_PIX_FMT_BGRA:
40  avctx->bits_per_coded_sample = 32;
41  break;
42  case AV_PIX_FMT_BGR24:
43  avctx->bits_per_coded_sample = 24;
44  break;
45  case AV_PIX_FMT_RGB555:
46  case AV_PIX_FMT_RGB565:
47  case AV_PIX_FMT_RGB444:
48  avctx->bits_per_coded_sample = 16;
49  break;
50  case AV_PIX_FMT_RGB8:
51  case AV_PIX_FMT_BGR8:
54  case AV_PIX_FMT_GRAY8:
55  case AV_PIX_FMT_PAL8:
56  avctx->bits_per_coded_sample = 8;
57  break;
59  avctx->bits_per_coded_sample = 1;
60  break;
61  }
62 
63  return 0;
64 }
65 
67  const AVFrame *pict, int *got_packet)
68 {
69  const AVFrame * const p = pict;
70  int n_bytes_image, n_bytes_per_row, n_bytes, i, n, hsize, ret;
71  const uint32_t *pal = NULL;
72  uint32_t palette256[256];
73  int pad_bytes_per_row, pal_entries = 0, compression = BMP_RGB;
74  int bit_count = avctx->bits_per_coded_sample;
75  uint8_t *ptr, *buf;
76 
77  switch (avctx->pix_fmt) {
78  case AV_PIX_FMT_RGB444:
79  compression = BMP_BITFIELDS;
80  pal = rgb444_masks; // abuse pal to hold color masks
81  pal_entries = 3;
82  break;
83  case AV_PIX_FMT_RGB565:
84  compression = BMP_BITFIELDS;
85  pal = rgb565_masks; // abuse pal to hold color masks
86  pal_entries = 3;
87  break;
88  case AV_PIX_FMT_RGB8:
89  case AV_PIX_FMT_BGR8:
92  case AV_PIX_FMT_GRAY8:
93  av_assert1(bit_count == 8);
94  avpriv_set_systematic_pal2(palette256, avctx->pix_fmt);
95  pal = palette256;
96  break;
97  case AV_PIX_FMT_PAL8:
98  pal = (uint32_t *)p->data[1];
99  break;
101  pal = monoblack_pal;
102  break;
103  }
104  if (pal && !pal_entries) pal_entries = 1 << bit_count;
105  n_bytes_per_row = ((int64_t)avctx->width * (int64_t)bit_count + 7LL) >> 3LL;
106  pad_bytes_per_row = (4 - n_bytes_per_row) & 3;
107  n_bytes_image = avctx->height * (n_bytes_per_row + pad_bytes_per_row);
108 
109  // STRUCTURE.field refer to the MSVC documentation for BITMAPFILEHEADER
110  // and related pages.
111 #define SIZE_BITMAPFILEHEADER 14
112 #define SIZE_BITMAPINFOHEADER 40
113  hsize = SIZE_BITMAPFILEHEADER + SIZE_BITMAPINFOHEADER + (pal_entries << 2);
114  n_bytes = n_bytes_image + hsize;
115  if ((ret = ff_get_encode_buffer(avctx, pkt, n_bytes, 0)) < 0)
116  return ret;
117  buf = pkt->data;
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 = pkt->data + hsize;
140  for(i = 0; i < avctx->height; i++) {
141  if (HAVE_BIGENDIAN && bit_count == 16) {
142  const uint16_t *src = (const uint16_t *) ptr;
143  for(n = 0; n < avctx->width; n++)
144  AV_WL16(buf + 2 * n, src[n]);
145  } else {
146  memcpy(buf, ptr, n_bytes_per_row);
147  }
148  buf += n_bytes_per_row;
149  memset(buf, 0, pad_bytes_per_row);
150  buf += pad_bytes_per_row;
151  ptr -= p->linesize[0]; // ... and go back
152  }
153 
154  *got_packet = 1;
155  return 0;
156 }
157 
159  .name = "bmp",
160  .long_name = NULL_IF_CONFIG_SMALL("BMP (Windows and OS/2 bitmap)"),
161  .type = AVMEDIA_TYPE_VIDEO,
162  .id = AV_CODEC_ID_BMP,
163  .capabilities = AV_CODEC_CAP_DR1,
164  .init = bmp_encode_init,
165  .encode2 = bmp_encode_frame,
166  .pix_fmts = (const enum AVPixelFormat[]){
172  },
173  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
174 };
rgb444_masks
static const uint32_t rgb444_masks[]
Definition: bmpenc.c:35
AVCodec
AVCodec.
Definition: codec.h:202
FF_CODEC_CAP_INIT_THREADSAFE
#define FF_CODEC_CAP_INIT_THREADSAFE
The codec does not modify any global variables in the init function, allowing to call the init functi...
Definition: internal.h:42
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:373
encode.h
AV_PIX_FMT_BGR24
@ AV_PIX_FMT_BGR24
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
AV_PIX_FMT_BGRA
@ AV_PIX_FMT_BGRA
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
Definition: pixfmt.h:95
BMP_RGB
@ BMP_RGB
Definition: bmp.h:26
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:317
SIZE_BITMAPINFOHEADER
#define SIZE_BITMAPINFOHEADER
AV_PIX_FMT_BGR8
@ AV_PIX_FMT_BGR8
packed RGB 3:3:2, 8bpp, (msb)2B 3G 3R(lsb)
Definition: pixfmt.h:83
avassert.h
pkt
AVPacket * pkt
Definition: movenc.c:59
av_cold
#define av_cold
Definition: attributes.h:90
AV_CODEC_ID_BMP
@ AV_CODEC_ID_BMP
Definition: codec_id.h:128
ff_bmp_encoder
const AVCodec ff_bmp_encoder
Definition: bmpenc.c:158
avpriv_set_systematic_pal2
int avpriv_set_systematic_pal2(uint32_t pal[256], enum AVPixelFormat pix_fmt)
Definition: imgutils.c:178
bmp.h
NULL
#define NULL
Definition: coverity.c:32
AV_PIX_FMT_MONOBLACK
@ AV_PIX_FMT_MONOBLACK
Y , 1bpp, 0 is black, 1 is white, in each byte pixels are ordered from the msb to the lsb.
Definition: pixfmt.h:76
src
#define src
Definition: vp8dsp.c:255
AV_PIX_FMT_RGB8
@ AV_PIX_FMT_RGB8
packed RGB 3:3:2, 8bpp, (msb)2R 3G 3B(lsb)
Definition: pixfmt.h:86
AV_PIX_FMT_GRAY8
@ AV_PIX_FMT_GRAY8
Y , 8bpp.
Definition: pixfmt.h:74
AV_PIX_FMT_BGR4_BYTE
@ AV_PIX_FMT_BGR4_BYTE
packed RGB 1:2:1, 8bpp, (msb)1B 2G 1R(lsb)
Definition: pixfmt.h:85
bmp_encode_init
static av_cold int bmp_encode_init(AVCodecContext *avctx)
Definition: bmpenc.c:37
monoblack_pal
static const uint32_t monoblack_pal[]
Definition: bmpenc.c:33
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
BMP_BITFIELDS
@ BMP_BITFIELDS
Definition: bmp.h:29
AV_WL16
#define AV_WL16(p, v)
Definition: intreadwrite.h:412
height
#define height
AVCodecContext::bits_per_coded_sample
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1418
bmp_encode_frame
static int bmp_encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *pict, int *got_packet)
Definition: bmpenc.c:66
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
av_assert1
#define av_assert1(cond)
assert() equivalent, that does not lie in speed critical code.
Definition: avassert.h:53
AV_PIX_FMT_RGB555
#define AV_PIX_FMT_RGB555
Definition: pixfmt.h:379
SIZE_BITMAPFILEHEADER
#define SIZE_BITMAPFILEHEADER
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:209
AV_PIX_FMT_RGB4_BYTE
@ AV_PIX_FMT_RGB4_BYTE
packed RGB 1:2:1, 8bpp, (msb)1R 2G 1B(lsb)
Definition: pixfmt.h:88
AVCodecContext::height
int height
Definition: avcodec.h:556
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:593
AV_PIX_FMT_RGB565
#define AV_PIX_FMT_RGB565
Definition: pixfmt.h:378
avcodec.h
AV_PIX_FMT_PAL8
@ AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
ret
ret
Definition: filter_design.txt:187
AVCodecContext
main external API structure.
Definition: avcodec.h:383
ff_get_encode_buffer
int ff_get_encode_buffer(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int flags)
Get a buffer for a packet.
Definition: encode.c:78
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:65
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVPacket
This structure stores compressed data.
Definition: packet.h:350
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:556
bytestream.h
imgutils.h
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:334
rgb565_masks
static const uint32_t rgb565_masks[]
Definition: bmpenc.c:34
AV_PIX_FMT_RGB444
#define AV_PIX_FMT_RGB444
Definition: pixfmt.h:380