png.c 13.2 KB
Newer Older
1 2 3
/*****************************************************************************
 * png.c: png decoder module making use of libpng.
 *****************************************************************************
Jean-Baptiste Kempf's avatar
Jean-Baptiste Kempf committed
4
 * Copyright (C) 1999-2001 VLC authors and VideoLAN
5 6 7 8
 * $Id$
 *
 * Authors: Gildas Bazin <gbazin@videolan.org>
 *
Jean-Baptiste Kempf's avatar
Jean-Baptiste Kempf committed
9 10 11
 * This program 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
12 13 14 15
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
Jean-Baptiste Kempf's avatar
Jean-Baptiste Kempf committed
16 17
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Lesser General Public License for more details.
18
 *
Jean-Baptiste Kempf's avatar
Jean-Baptiste Kempf committed
19 20 21
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22 23 24 25 26
 *****************************************************************************/

/*****************************************************************************
 * Preamble
 *****************************************************************************/
27 28 29 30
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

31
#include <vlc_common.h>
32
#include <vlc_plugin.h>
33
#include <vlc_codec.h>
34 35
#include <png.h>

Tristan Matthews's avatar
Tristan Matthews committed
36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54
/* PNG_SYS_COMMON_MEMBERS:
 * members common to encoder and decoder descriptors
 */
#define PNG_SYS_COMMON_MEMBERS                              \
/**@{*/                                                     \
    bool b_error;                                           \
    vlc_object_t *p_obj;                                    \
/**@}*/                                                     \

/*
 * png common descriptor
 */
struct png_sys_t
{
    PNG_SYS_COMMON_MEMBERS
};

typedef struct png_sys_t png_sys_t;

55 56 57 58 59
/*****************************************************************************
 * decoder_sys_t : png decoder descriptor
 *****************************************************************************/
struct decoder_sys_t
{
Tristan Matthews's avatar
Tristan Matthews committed
60
    PNG_SYS_COMMON_MEMBERS
61 62 63 64 65 66 67 68
};

/*****************************************************************************
 * Local prototypes
 *****************************************************************************/
static int  OpenDecoder   ( vlc_object_t * );
static void CloseDecoder  ( vlc_object_t * );

69
static int DecodeBlock  ( decoder_t *, block_t * );
70

Tristan Matthews's avatar
Tristan Matthews committed
71 72 73 74 75 76 77 78 79 80 81 82 83 84
/*
 * png encoder descriptor
 */
struct encoder_sys_t
{
    PNG_SYS_COMMON_MEMBERS
    int i_blocksize;
};

static int  OpenEncoder(vlc_object_t *);
static void CloseEncoder(vlc_object_t *);

static block_t *EncodeBlock(encoder_t *, picture_t *);

85 86 87
/*****************************************************************************
 * Module descriptor
 *****************************************************************************/
88 89 90 91
vlc_module_begin ()
    set_category( CAT_INPUT )
    set_subcategory( SUBCAT_INPUT_VCODEC )
    set_description( N_("PNG video decoder") )
92
    set_capability( "video decoder", 1000 )
93 94
    set_callbacks( OpenDecoder, CloseDecoder )
    add_shortcut( "png" )
Tristan Matthews's avatar
Tristan Matthews committed
95 96 97 98 99 100 101 102

    /* encoder submodule */
    add_submodule()
    add_shortcut("png")
    set_section(N_("Encoding"), NULL)
    set_description(N_("PNG video encoder"))
    set_capability("encoder", 1000)
    set_callbacks(OpenEncoder, CloseEncoder)
103
vlc_module_end ()
104 105 106 107 108 109 110 111

/*****************************************************************************
 * OpenDecoder: probe the decoder and return score
 *****************************************************************************/
static int OpenDecoder( vlc_object_t *p_this )
{
    decoder_t *p_dec = (decoder_t*)p_this;

112
    if( p_dec->fmt_in.i_codec != VLC_CODEC_PNG &&
Derk-Jan Hartman's avatar
Derk-Jan Hartman committed
113
        p_dec->fmt_in.i_codec != VLC_FOURCC('M','P','N','G') )
114 115 116 117 118
    {
        return VLC_EGENERIC;
    }

    /* Allocate the memory needed to store the decoder's structure */
119 120
    p_dec->p_sys = malloc( sizeof(decoder_sys_t) );
    if( p_dec->p_sys == NULL )
121
        return VLC_ENOMEM;
122

Tristan Matthews's avatar
Tristan Matthews committed
123 124
    p_dec->p_sys->p_obj = p_this;

125
    /* Set output properties */
126
    p_dec->fmt_out.i_codec = VLC_CODEC_RGBA;
127 128

    /* Set callbacks */
129
    p_dec->pf_decode = DecodeBlock;
130 131 132 133 134 135 136

    return VLC_SUCCESS;
}

static void user_read( png_structp p_png, png_bytep data, png_size_t i_length )
{
    block_t *p_block = (block_t *)png_get_io_ptr( p_png );
137 138 139 140 141
    if( i_length > p_block->i_buffer ) {
        png_error( p_png, "not enough data" );
        return;
    }

142 143 144 145 146
    memcpy( data, p_block->p_buffer, i_length );
    p_block->p_buffer += i_length;
    p_block->i_buffer -= i_length;
}

Tristan Matthews's avatar
Tristan Matthews committed
147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169
static void user_flush( png_structp p_png )
{
    /* noop */
    (void) p_png;
}

static void user_write( png_structp p_png, png_bytep data, png_size_t i_length )
{
    block_t *p_block = (block_t *)png_get_io_ptr( p_png );
    if( i_length > p_block->i_buffer ) {
        char err_str[64];
        snprintf( err_str, sizeof(err_str),
                  "block size %zu too small for %zu encoded bytes",
                  p_block->i_buffer, i_length );
        png_error( p_png, err_str );
        return;
    }

    memcpy( p_block->p_buffer, data, i_length );
    p_block->p_buffer += i_length;
    p_block->i_buffer -= i_length;
}

170 171
static void user_error( png_structp p_png, png_const_charp error_msg )
{
Tristan Matthews's avatar
Tristan Matthews committed
172 173 174
    png_sys_t *p_sys = (png_sys_t *)png_get_error_ptr( p_png );
    p_sys->b_error = true;
    msg_Err( p_sys->p_obj, "%s", error_msg );
175 176 177 178
}

static void user_warning( png_structp p_png, png_const_charp warning_msg )
{
Tristan Matthews's avatar
Tristan Matthews committed
179 180
    png_sys_t *p_sys = (png_sys_t *)png_get_error_ptr( p_png );
    msg_Warn( p_sys->p_obj, "%s", warning_msg );
181 182 183 184 185 186 187
}

/****************************************************************************
 * DecodeBlock: the whole thing
 ****************************************************************************
 * This function must be fed with a complete compressed frame.
 ****************************************************************************/
188
static int DecodeBlock( decoder_t *p_dec, block_t *p_block )
189 190 191 192 193 194 195 196 197 198
{
    decoder_sys_t *p_sys = p_dec->p_sys;
    picture_t *p_pic = 0;

    png_uint_32 i_width, i_height;
    int i_color_type, i_interlace_type, i_compression_type, i_filter_type;
    int i_bit_depth, i;

    png_structp p_png;
    png_infop p_info, p_end_info;
199
    png_bytep *volatile p_row_pointers = NULL;
200

201 202
    if( !p_block ) /* No Drain */
        return VLCDEC_SUCCESS;
203

204
    p_sys->b_error = false;
205

206
    if( p_block->i_flags & BLOCK_FLAG_CORRUPTED )
207
    {
208 209
        block_Release( p_block );
        return VLCDEC_SUCCESS;
210 211
    }

212
    p_png = png_create_read_struct( PNG_LIBPNG_VER_STRING, 0, 0, 0 );
213 214
    if( p_png == NULL )
    {
215 216
        block_Release( p_block );
        return VLCDEC_SUCCESS;
217
    }
218

219
    p_info = png_create_info_struct( p_png );
220 221
    if( p_info == NULL )
    {
222
        png_destroy_read_struct( &p_png, NULL, NULL );
223 224
        block_Release( p_block );
        return VLCDEC_SUCCESS;
225 226
    }

227
    p_end_info = png_create_info_struct( p_png );
228 229
    if( p_end_info == NULL )
    {
230
        png_destroy_read_struct( &p_png, &p_info, NULL );
231 232
        block_Release( p_block );
        return VLCDEC_SUCCESS;
233
    }
234

235 236 237 238
    /* libpng longjmp's there in case of error */
    if( setjmp( png_jmpbuf( p_png ) ) )
        goto error;

239 240 241 242 243 244 245 246 247 248 249 250
    png_set_read_fn( p_png, (void *)p_block, user_read );
    png_set_error_fn( p_png, (void *)p_dec, user_error, user_warning );

    png_read_info( p_png, p_info );
    if( p_sys->b_error ) goto error;

    png_get_IHDR( p_png, p_info, &i_width, &i_height,
                  &i_bit_depth, &i_color_type, &i_interlace_type,
                  &i_compression_type, &i_filter_type);
    if( p_sys->b_error ) goto error;

    /* Set output properties */
251
    p_dec->fmt_out.i_codec = VLC_CODEC_RGBA;
252 253
    p_dec->fmt_out.video.i_visible_width = p_dec->fmt_out.video.i_width = i_width;
    p_dec->fmt_out.video.i_visible_height = p_dec->fmt_out.video.i_height = i_height;
254 255
    p_dec->fmt_out.video.i_sar_num = 1;
    p_dec->fmt_out.video.i_sar_den = 1;
256 257 258 259 260 261 262

    if( i_color_type == PNG_COLOR_TYPE_PALETTE )
        png_set_palette_to_rgb( p_png );

    if( i_color_type == PNG_COLOR_TYPE_GRAY ||
        i_color_type == PNG_COLOR_TYPE_GRAY_ALPHA )
          png_set_gray_to_rgb( p_png );
263
    if( i_color_type & PNG_COLOR_MASK_ALPHA )
264
        png_set_alpha_mode( p_png, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB );
265 266

    /* Strip to 8 bits per channel */
267 268 269 270 271 272 273 274
    if( i_bit_depth == 16 )
    {
#if PNG_LIBPNG_VER >= 10504
        png_set_scale_16( p_png );
#else
        png_set_strip_16( p_png );
#endif
    }
275 276 277 278 279 280 281

    if( png_get_valid( p_png, p_info, PNG_INFO_tRNS ) )
    {
        png_set_tRNS_to_alpha( p_png );
    }
    else if( !(i_color_type & PNG_COLOR_MASK_ALPHA) )
    {
282
        p_dec->fmt_out.i_codec = VLC_CODEC_RGB24;
283 284 285
    }

    /* Get a new picture */
286 287
    if( decoder_UpdateVideoFormat( p_dec ) )
        goto error;
288
    p_pic = decoder_NewPicture( p_dec );
289 290 291
    if( !p_pic ) goto error;

    /* Decode picture */
292
    p_row_pointers = vlc_alloc( i_height, sizeof(png_bytep) );
293 294
    if( !p_row_pointers )
        goto error;
295 296 297 298 299 300 301 302 303 304 305
    for( i = 0; i < (int)i_height; i++ )
        p_row_pointers[i] = p_pic->p->p_pixels + p_pic->p->i_pitch * i;

    png_read_image( p_png, p_row_pointers );
    if( p_sys->b_error ) goto error;
    png_read_end( p_png, p_end_info );
    if( p_sys->b_error ) goto error;

    png_destroy_read_struct( &p_png, &p_info, &p_end_info );
    free( p_row_pointers );

306
    p_pic->date = p_block->i_pts > VLC_TS_INVALID ? p_block->i_pts : p_block->i_dts;
Derk-Jan Hartman's avatar
Derk-Jan Hartman committed
307

308 309 310
    block_Release( p_block );
    decoder_QueueVideo( p_dec, p_pic );
    return VLCDEC_SUCCESS;
311 312 313

 error:

314
    free( p_row_pointers );
315
    png_destroy_read_struct( &p_png, &p_info, &p_end_info );
316 317
    block_Release( p_block );
    return VLCDEC_SUCCESS;
318 319 320 321 322 323 324 325 326 327 328 329
}

/*****************************************************************************
 * CloseDecoder: png decoder destruction
 *****************************************************************************/
static void CloseDecoder( vlc_object_t *p_this )
{
    decoder_t *p_dec = (decoder_t *)p_this;
    decoder_sys_t *p_sys = p_dec->p_sys;

    free( p_sys );
}
Tristan Matthews's avatar
Tristan Matthews committed
330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348

static int OpenEncoder(vlc_object_t *p_this)
{
    encoder_t *p_enc = (encoder_t *) p_this;

    if( p_enc->fmt_out.i_codec != VLC_CODEC_PNG )
        return VLC_EGENERIC;

    /* Allocate the memory needed to store the encoder's structure */
    p_enc->p_sys = malloc( sizeof(encoder_sys_t) );
    if( p_enc->p_sys  == NULL )
        return VLC_ENOMEM;

    p_enc->p_sys->p_obj = p_this;

    p_enc->p_sys->i_blocksize = 3 * p_enc->fmt_in.video.i_visible_width *
        p_enc->fmt_in.video.i_visible_height;

    p_enc->fmt_in.i_codec = VLC_CODEC_RGB24;
349 350 351
    p_enc->fmt_in.video.i_bmask = 0;
    video_format_FixRgb( &p_enc->fmt_in.video );

Tristan Matthews's avatar
Tristan Matthews committed
352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381
    p_enc->pf_encode_video = EncodeBlock;

    return VLC_SUCCESS;
}

/*
 * EncodeBlock
 */
static block_t *EncodeBlock(encoder_t *p_enc, picture_t *p_pic)
{
    encoder_sys_t *p_sys = p_enc->p_sys;

    if( unlikely( !p_pic ) )
    {
        return NULL;
    }

    block_t *p_block = block_Alloc( p_sys->i_blocksize );
    if( p_block == NULL )
    {
        return NULL;
    }

    png_structp p_png = png_create_write_struct( PNG_LIBPNG_VER_STRING, 0, 0, 0 );
    if( p_png == NULL )
    {
        block_Release( p_block );
        return NULL;
    }

382 383 384 385 386
    /* Disable filtering to speed-up encoding */
    png_set_filter( p_png, 0, PNG_NO_FILTERS );
    /* 1 == best speed */
    png_set_compression_level( p_png, 1 );

Tristan Matthews's avatar
Tristan Matthews committed
387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405
    /* save buffer start */
    uint8_t *p_start = p_block->p_buffer;
    size_t i_start = p_block->i_buffer;

    p_sys->b_error = false;
    png_infop p_info = NULL;

    /* libpng longjmp's there in case of error */
    if( setjmp( png_jmpbuf( p_png ) ) )
        goto error;

    png_set_write_fn( p_png, p_block, user_write, user_flush );
    png_set_error_fn( p_png, p_enc, user_error, user_warning );

    p_info = png_create_info_struct( p_png );
    if( p_info == NULL )
        goto error;

    png_set_IHDR( p_png, p_info,
406 407
            p_enc->fmt_in.video.i_visible_width,
            p_enc->fmt_in.video.i_visible_height,
Tristan Matthews's avatar
Tristan Matthews committed
408 409 410 411 412 413 414 415 416
            8, PNG_COLOR_TYPE_RGB, PNG_INTERLACE_NONE,
            PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT );
    if( p_sys->b_error ) goto error;

    png_write_info( p_png, p_info );
    if( p_sys->b_error ) goto error;

    /* Encode picture */

417
    for( int i = 0; i < p_pic->p->i_visible_lines; i++ )
Tristan Matthews's avatar
Tristan Matthews committed
418
    {
419
        png_write_row( p_png, p_pic->p->p_pixels + (i * p_pic->p->i_pitch) );
Tristan Matthews's avatar
Tristan Matthews committed
420 421 422
        if( p_sys->b_error ) goto error;
    }

Hannes Domani's avatar
Hannes Domani committed
423
    png_write_end( p_png, p_info );
Tristan Matthews's avatar
Tristan Matthews committed
424 425 426 427 428 429
    if( p_sys->b_error ) goto error;

    png_destroy_write_struct( &p_png, &p_info );

    /* restore original buffer position */
    p_block->p_buffer = p_start;
430
    p_block->i_buffer = i_start - p_block->i_buffer;
431 432 433

    p_block->i_dts = p_block->i_pts = p_pic->date;

Tristan Matthews's avatar
Tristan Matthews committed
434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453
    return p_block;

 error:

    png_destroy_write_struct( &p_png, p_info ? &p_info : NULL );

    block_Release(p_block);
    return NULL;
}

/*****************************************************************************
 * CloseEncoder: png encoder destruction
 *****************************************************************************/
static void CloseEncoder( vlc_object_t *p_this )
{
    encoder_t *p_enc = (encoder_t *)p_this;
    encoder_sys_t *p_sys = p_enc->p_sys;

    free( p_sys );
}