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 "codec_internal.h"
31 #include "encode.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 
37 static av_cold int bmp_encode_init(AVCodecContext *avctx){
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:
52  case AV_PIX_FMT_RGB4_BYTE:
53  case AV_PIX_FMT_BGR4_BYTE:
54  case AV_PIX_FMT_GRAY8:
55  case AV_PIX_FMT_PAL8:
56  avctx->bits_per_coded_sample = 8;
57  break;
58  case AV_PIX_FMT_MONOBLACK:
59  avctx->bits_per_coded_sample = 1;
60  break;
61  }
62 
63  return 0;
64 }
65 
66 static int bmp_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
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  const uint8_t *ptr;
76  uint8_t *buf;
77 
78  switch (avctx->pix_fmt) {
79  case AV_PIX_FMT_RGB444:
80  compression = BMP_BITFIELDS;
81  pal = rgb444_masks; // abuse pal to hold color masks
82  pal_entries = 3;
83  break;
84  case AV_PIX_FMT_RGB565:
85  compression = BMP_BITFIELDS;
86  pal = rgb565_masks; // abuse pal to hold color masks
87  pal_entries = 3;
88  break;
89  case AV_PIX_FMT_RGB8:
90  case AV_PIX_FMT_BGR8:
91  case AV_PIX_FMT_RGB4_BYTE:
92  case AV_PIX_FMT_BGR4_BYTE:
93  case AV_PIX_FMT_GRAY8:
94  av_assert1(bit_count == 8);
95  avpriv_set_systematic_pal2(palette256, avctx->pix_fmt);
96  pal = palette256;
97  break;
98  case AV_PIX_FMT_PAL8:
99  pal = (uint32_t *)p->data[1];
100  break;
101  case AV_PIX_FMT_MONOBLACK:
102  pal = monoblack_pal;
103  break;
104  }
105  if (pal && !pal_entries) pal_entries = 1 << bit_count;
106  n_bytes_per_row = ((int64_t)avctx->width * (int64_t)bit_count + 7LL) >> 3LL;
107  pad_bytes_per_row = (4 - n_bytes_per_row) & 3;
108  n_bytes_image = avctx->height * (n_bytes_per_row + pad_bytes_per_row);
109 
110  // STRUCTURE.field refer to the MSVC documentation for BITMAPFILEHEADER
111  // and related pages.
112 #define SIZE_BITMAPFILEHEADER 14
113 #define SIZE_BITMAPINFOHEADER 40
114  hsize = SIZE_BITMAPFILEHEADER + SIZE_BITMAPINFOHEADER + (pal_entries << 2);
115  n_bytes = n_bytes_image + hsize;
116  if ((ret = ff_get_encode_buffer(avctx, pkt, n_bytes, 0)) < 0)
117  return ret;
118  buf = pkt->data;
119  bytestream_put_byte(&buf, 'B'); // BITMAPFILEHEADER.bfType
120  bytestream_put_byte(&buf, 'M'); // do.
121  bytestream_put_le32(&buf, n_bytes); // BITMAPFILEHEADER.bfSize
122  bytestream_put_le16(&buf, 0); // BITMAPFILEHEADER.bfReserved1
123  bytestream_put_le16(&buf, 0); // BITMAPFILEHEADER.bfReserved2
124  bytestream_put_le32(&buf, hsize); // BITMAPFILEHEADER.bfOffBits
125  bytestream_put_le32(&buf, SIZE_BITMAPINFOHEADER); // BITMAPINFOHEADER.biSize
126  bytestream_put_le32(&buf, avctx->width); // BITMAPINFOHEADER.biWidth
127  bytestream_put_le32(&buf, avctx->height); // BITMAPINFOHEADER.biHeight
128  bytestream_put_le16(&buf, 1); // BITMAPINFOHEADER.biPlanes
129  bytestream_put_le16(&buf, bit_count); // BITMAPINFOHEADER.biBitCount
130  bytestream_put_le32(&buf, compression); // BITMAPINFOHEADER.biCompression
131  bytestream_put_le32(&buf, n_bytes_image); // BITMAPINFOHEADER.biSizeImage
132  bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biXPelsPerMeter
133  bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biYPelsPerMeter
134  bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biClrUsed
135  bytestream_put_le32(&buf, 0); // BITMAPINFOHEADER.biClrImportant
136  for (i = 0; i < pal_entries; i++)
137  bytestream_put_le32(&buf, pal[i] & 0xFFFFFF);
138  // BMP files are bottom-to-top so we start from the end...
139  ptr = p->data[0] + (avctx->height - 1) * p->linesize[0];
140  buf = pkt->data + hsize;
141  for(i = 0; i < avctx->height; i++) {
142  if (HAVE_BIGENDIAN && bit_count == 16) {
143  const uint16_t *src = (const uint16_t *) ptr;
144  for(n = 0; n < avctx->width; n++)
145  AV_WL16(buf + 2 * 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 
155  *got_packet = 1;
156  return 0;
157 }
158 
159 const FFCodec ff_bmp_encoder = {
160  .p.name = "bmp",
161  .p.long_name = NULL_IF_CONFIG_SMALL("BMP (Windows and OS/2 bitmap)"),
162  .p.type = AVMEDIA_TYPE_VIDEO,
163  .p.id = AV_CODEC_ID_BMP,
164  .p.capabilities = AV_CODEC_CAP_DR1,
165  .init = bmp_encode_init,
166  FF_CODEC_ENCODE_CB(bmp_encode_frame),
167  .p.pix_fmts = (const enum AVPixelFormat[]){
168  AV_PIX_FMT_BGRA, AV_PIX_FMT_BGR24,
169  AV_PIX_FMT_RGB565, AV_PIX_FMT_RGB555, AV_PIX_FMT_RGB444,
170  AV_PIX_FMT_RGB8, AV_PIX_FMT_BGR8, AV_PIX_FMT_RGB4_BYTE, AV_PIX_FMT_BGR4_BYTE, AV_PIX_FMT_GRAY8, AV_PIX_FMT_PAL8,
171  AV_PIX_FMT_MONOBLACK,
172  AV_PIX_FMT_NONE
173  },
174 };
rgb444_masks
static const uint32_t rgb444_masks[]
Definition: bmpenc.c:35
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
ff_bmp_encoder
const FFCodec ff_bmp_encoder
Definition: bmpenc.c:159
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:325
AVPacket::data
uint8_t * data
Definition: packet.h:374
encode.h
FFCodec
Definition: codec_internal.h:118
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:346
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:122
FF_CODEC_ENCODE_CB
#define FF_CODEC_ENCODE_CB(func)
Definition: codec_internal.h:269
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
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
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
codec_internal.h
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:1450
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:269
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:396
SIZE_BITMAPFILEHEADER
#define SIZE_BITMAPFILEHEADER
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:211
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:571
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:608
AV_PIX_FMT_RGB565
#define AV_PIX_FMT_RGB565
Definition: pixfmt.h:395
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:398
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:79
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:351
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:571
bytestream.h
imgutils.h
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, a positive or negative value, which is typically indicating the size in bytes of each pict...
Definition: frame.h:370
rgb565_masks
static const uint32_t rgb565_masks[]
Definition: bmpenc.c:34
AV_PIX_FMT_RGB444
#define AV_PIX_FMT_RGB444
Definition: pixfmt.h:397
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