FFmpeg
anm.c
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1 /*
2  * Deluxe Paint Animation decoder
3  * Copyright (c) 2009 Peter Ross
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * Deluxe Paint Animation decoder
25  */
26 
27 #include "avcodec.h"
28 #include "bytestream.h"
29 #include "codec_internal.h"
30 #include "decode.h"
31 
32 typedef struct AnmContext {
35 } AnmContext;
36 
38 {
39  AnmContext *s = avctx->priv_data;
40  GetByteContext gb;
41  int i;
42 
43  if (avctx->extradata_size < 16 * 8 + 4 * 256)
44  return AVERROR_INVALIDDATA;
45 
46  avctx->pix_fmt = AV_PIX_FMT_PAL8;
47 
48  s->frame = av_frame_alloc();
49  if (!s->frame)
50  return AVERROR(ENOMEM);
51 
52  bytestream2_init(&gb, avctx->extradata, avctx->extradata_size);
53  bytestream2_skipu(&gb, 16 * 8);
54  for (i = 0; i < 256; i++)
55  s->palette[i] = (0xFFU << 24) | bytestream2_get_le32u(&gb);
56 
57  return 0;
58 }
59 
60 /**
61  * Perform decode operation
62  * @param dst pointer to destination image buffer
63  * @param dst_end pointer to end of destination image buffer
64  * @param gb GetByteContext (optional, see below)
65  * @param pixel Fill color (optional, see below)
66  * @param count Pixel count
67  * @param x Pointer to x-axis counter
68  * @param width Image width
69  * @param linesize Destination image buffer linesize
70  * @return non-zero if destination buffer is exhausted
71  *
72  * a copy operation is achieved when 'gb' is set
73  * a fill operation is achieved when 'gb' is null and pixel is >= 0
74  * a skip operation is achieved when 'gb' is null and pixel is < 0
75  */
76 static inline int op(uint8_t **dst, const uint8_t *dst_end,
77  GetByteContext *gb,
78  int pixel, int count,
79  int *x, int width, int linesize)
80 {
81  int remaining = width - *x;
82  while(count > 0) {
83  int striplen = FFMIN(count, remaining);
84  if (gb) {
85  if (bytestream2_get_bytes_left(gb) < striplen)
86  goto exhausted;
87  bytestream2_get_bufferu(gb, *dst, striplen);
88  } else if (pixel >= 0)
89  memset(*dst, pixel, striplen);
90  *dst += striplen;
91  remaining -= striplen;
92  count -= striplen;
93  if (remaining <= 0) {
94  *dst += linesize - width;
95  remaining = width;
96  }
97  if (linesize > 0) {
98  if (*dst >= dst_end) goto exhausted;
99  } else {
100  if (*dst <= dst_end) goto exhausted;
101  }
102  }
103  *x = width - remaining;
104  return 0;
105 
106 exhausted:
107  *x = width - remaining;
108  return 1;
109 }
110 
111 static int decode_frame(AVCodecContext *avctx, AVFrame *rframe,
112  int *got_frame, AVPacket *avpkt)
113 {
114  AnmContext *s = avctx->priv_data;
115  const int buf_size = avpkt->size;
116  uint8_t *dst, *dst_end;
117  GetByteContext gb;
118  int count, ret, x = 0;
119 
120  if (buf_size < 7)
121  return AVERROR_INVALIDDATA;
122 
123  if ((ret = ff_reget_buffer(avctx, s->frame, 0)) < 0)
124  return ret;
125  dst = s->frame->data[0];
126  dst_end = s->frame->data[0] + s->frame->linesize[0]*avctx->height;
127 
128  bytestream2_init(&gb, avpkt->data, buf_size);
129 
130  if (bytestream2_get_byte(&gb) != 0x42) {
131  avpriv_request_sample(avctx, "Unknown record type");
132  return AVERROR_INVALIDDATA;
133  }
134  if (bytestream2_get_byte(&gb)) {
135  avpriv_request_sample(avctx, "Padding bytes");
136  return AVERROR_PATCHWELCOME;
137  }
138  bytestream2_skip(&gb, 2);
139 
140  do {
141  /* if statements are ordered by probability */
142 #define OP(gb, pixel, count) \
143  op(&dst, dst_end, (gb), (pixel), (count), &x, avctx->width, s->frame->linesize[0])
144 
145  int type = bytestream2_get_byte(&gb);
146  count = type & 0x7F;
147  type >>= 7;
148  if (count) {
149  if (OP(type ? NULL : &gb, -1, count)) break;
150  } else if (!type) {
151  int pixel;
152  count = bytestream2_get_byte(&gb); /* count==0 gives nop */
153  pixel = bytestream2_get_byte(&gb);
154  if (OP(NULL, pixel, count)) break;
155  } else {
156  int pixel;
157  type = bytestream2_get_le16(&gb);
158  count = type & 0x3FFF;
159  type >>= 14;
160  if (!count) {
161  if (type == 0)
162  break; // stop
163  if (type == 2) {
164  avpriv_request_sample(avctx, "Unknown opcode");
165  return AVERROR_PATCHWELCOME;
166  }
167  continue;
168  }
169  pixel = type == 3 ? bytestream2_get_byte(&gb) : -1;
170  if (type == 1) count += 0x4000;
171  if (OP(type == 2 ? &gb : NULL, pixel, count)) break;
172  }
173  } while (bytestream2_get_bytes_left(&gb) > 0);
174 
175  memcpy(s->frame->data[1], s->palette, AVPALETTE_SIZE);
176 
177  *got_frame = 1;
178  if ((ret = av_frame_ref(rframe, s->frame)) < 0)
179  return ret;
180 
181  return buf_size;
182 }
183 
185 {
186  AnmContext *s = avctx->priv_data;
187 
188  av_frame_free(&s->frame);
189  return 0;
190 }
191 
193  .p.name = "anm",
194  CODEC_LONG_NAME("Deluxe Paint Animation"),
195  .p.type = AVMEDIA_TYPE_VIDEO,
196  .p.id = AV_CODEC_ID_ANM,
197  .priv_data_size = sizeof(AnmContext),
198  .init = decode_init,
199  .close = decode_end,
201  .p.capabilities = AV_CODEC_CAP_DR1,
202 };
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
AnmContext::frame
AVFrame * frame
Definition: anm.c:33
ff_anm_decoder
const FFCodec ff_anm_decoder
Definition: anm.c:192
GetByteContext
Definition: bytestream.h:33
bytestream2_skipu
static av_always_inline void bytestream2_skipu(GetByteContext *g, unsigned int size)
Definition: bytestream.h:174
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:88
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
AVPacket::data
uint8_t * data
Definition: packet.h:522
FFCodec
Definition: codec_internal.h:127
bytestream2_skip
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
AnmContext
Definition: anm.c:32
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:76
av_cold
#define av_cold
Definition: attributes.h:90
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:524
width
#define width
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:287
s
#define s(width, name)
Definition: cbs_vp9.c:198
op
static int op(uint8_t **dst, const uint8_t *dst_end, GetByteContext *gb, int pixel, int count, int *x, int width, int linesize)
Perform decode operation.
Definition: anm.c:76
decode.h
AnmContext::palette
int palette[AVPALETTE_COUNT]
Definition: anm.c:34
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:272
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
pixel
uint8_t pixel
Definition: tiny_ssim.c:41
AVPALETTE_SIZE
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
AV_CODEC_ID_ANM
@ AV_CODEC_ID_ANM
Definition: codec_id.h:186
AVPALETTE_COUNT
#define AVPALETTE_COUNT
Definition: pixfmt.h:33
bytestream2_get_bytes_left
static av_always_inline int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:158
init
int(* init)(AVBSFContext *ctx)
Definition: dts2pts.c:365
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
AVPacket::size
int size
Definition: packet.h:523
av_frame_ref
int av_frame_ref(AVFrame *dst, const AVFrame *src)
Set up a new reference to the data described by the source frame.
Definition: frame.c:312
codec_internal.h
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:523
decode_frame
static int decode_frame(AVCodecContext *avctx, AVFrame *rframe, int *got_frame, AVPacket *avpkt)
Definition: anm.c:111
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
decode_init
static av_cold int decode_init(AVCodecContext *avctx)
Definition: anm.c:37
AVCodecContext::height
int height
Definition: avcodec.h:618
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:657
avcodec.h
AV_PIX_FMT_PAL8
@ AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:84
ff_reget_buffer
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Identical in function to ff_get_buffer(), except it reuses the existing buffer if available.
Definition: decode.c:1677
ret
ret
Definition: filter_design.txt:187
AVCodecContext
main external API structure.
Definition: avcodec.h:445
OP
#define OP(gb, pixel, count)
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
bytestream2_get_bufferu
static av_always_inline unsigned int bytestream2_get_bufferu(GetByteContext *g, uint8_t *dst, unsigned int size)
Definition: bytestream.h:277
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:36
AVPacket
This structure stores compressed data.
Definition: packet.h:499
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:472
bytestream.h
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
decode_end
static av_cold int decode_end(AVCodecContext *avctx)
Definition: anm.c:184
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61