libavcodec/targa.c - third_party/ffmpeg - Git at Google

 /*
  * Targa (.tga) image decoder
  * Copyright (c) 2006 Konstantin Shishkov
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg 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.
  *
  * FFmpeg 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 FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */

 #include "libavutil/intreadwrite.h"
 #include "libavutil/imgutils.h"
 #include "avcodec.h"
 #include "bytestream.h"
 #include "internal.h"
 #include "targa.h"

 typedef struct TargaContext {
     GetByteContext gb;
 } TargaContext;

 static uint8_t *advance_line(uint8_t *start, uint8_t *line,
                              int stride, int *y, int h, int interleave)
 {
     *y += interleave;

     if (*y < h) {
         return line + interleave * stride;
     } else {
         *y = (*y + 1) & (interleave - 1);
         if (*y && *y < h) {
             return start + *y * stride;
         } else {
             return NULL;
         }
     }
 }

 static int targa_decode_rle(AVCodecContext *avctx, TargaContext *s,
                             uint8_t *start, int w, int h, int stride,
                             int bpp, int interleave)
 {
     int x, y;
     int depth = (bpp + 1) >> 3;
     int type, count;
     uint8_t *line = start;
     uint8_t *dst  = line;

     x = y = count = 0;
     while (dst) {
         if (bytestream2_get_bytes_left(&s->gb) <= 0) {
             av_log(avctx, AV_LOG_ERROR,
                    "Ran ouf of data before end-of-image\n");
             return AVERROR_INVALIDDATA;
         }
         type  = bytestream2_get_byteu(&s->gb);
         count = (type & 0x7F) + 1;
         type &= 0x80;
         if (!type) {
             do {
                 int n  = FFMIN(count, w - x);
                 bytestream2_get_buffer(&s->gb, dst, n * depth);
                 count -= n;
                 dst   += n * depth;
                 x     += n;
                 if (x == w) {
                     x    = 0;
                     dst = line = advance_line(start, line, stride, &y, h, interleave);
                 }
             } while (dst && count > 0);
         } else {
             uint8_t tmp[4];
             bytestream2_get_buffer(&s->gb, tmp, depth);
             do {
                 int n  = FFMIN(count, w - x);
                 count -= n;
                 x     += n;
                 do {
                     memcpy(dst, tmp, depth);
                     dst += depth;
                 } while (--n);
                 if (x == w) {
                     x    = 0;
                     dst = line = advance_line(start, line, stride, &y, h, interleave);
                 }
             } while (dst && count > 0);
         }
     }

     if (count) {
         av_log(avctx, AV_LOG_ERROR, "Packet went out of bounds\n");
         return AVERROR_INVALIDDATA;
     }

     return 0;
 }

 static int decode_frame(AVCodecContext *avctx,
                         void *data, int *got_frame,
                         AVPacket *avpkt)
 {
     TargaContext * const s = avctx->priv_data;
     AVFrame * const p = data;
     uint8_t *dst;
     int stride;
     int idlen, pal, compr, y, w, h, bpp, flags, ret;
     int first_clr, colors, csize;
     int interleave;

     bytestream2_init(&s->gb, avpkt->data, avpkt->size);

     /* parse image header */
     idlen     = bytestream2_get_byte(&s->gb);
     pal       = bytestream2_get_byte(&s->gb);
     compr     = bytestream2_get_byte(&s->gb);
     first_clr = bytestream2_get_le16(&s->gb);
     colors    = bytestream2_get_le16(&s->gb);
     csize     = bytestream2_get_byte(&s->gb);
     bytestream2_skip(&s->gb, 4); /* 2: x, 2: y */
     w         = bytestream2_get_le16(&s->gb);
     h         = bytestream2_get_le16(&s->gb);
     bpp       = bytestream2_get_byte(&s->gb);

     if (bytestream2_get_bytes_left(&s->gb) <= idlen) {
         av_log(avctx, AV_LOG_ERROR,
                 "Not enough data to read header\n");
         return AVERROR_INVALIDDATA;
     }

     flags     = bytestream2_get_byte(&s->gb);

     if (!pal && (first_clr || colors || csize)) {
         av_log(avctx, AV_LOG_WARNING, "File without colormap has colormap information set.\n");
         // specification says we should ignore those value in this case
         first_clr = colors = csize = 0;
     }

     // skip identifier if any
     bytestream2_skip(&s->gb, idlen);

     switch (bpp) {
     case 8:
         avctx->pix_fmt = ((compr & (~TGA_RLE)) == TGA_BW) ? AV_PIX_FMT_GRAY8 : AV_PIX_FMT_PAL8;
         break;
     case 15:
     case 16:
         avctx->pix_fmt = AV_PIX_FMT_RGB555LE;
         break;
     case 24:
         avctx->pix_fmt = AV_PIX_FMT_BGR24;
         break;
     case 32:
         avctx->pix_fmt = AV_PIX_FMT_BGRA;
         break;
     default:
         av_log(avctx, AV_LOG_ERROR, "Bit depth %i is not supported\n", bpp);
         return AVERROR_INVALIDDATA;
     }

     if (colors && (colors + first_clr) > 256) {
         av_log(avctx, AV_LOG_ERROR, "Incorrect palette: %i colors with offset %i\n", colors, first_clr);
         return AVERROR_INVALIDDATA;
     }

     if ((ret = ff_set_dimensions(avctx, w, h)) < 0)
         return ret;

     if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
         return ret;
     p->pict_type = AV_PICTURE_TYPE_I;

     if (flags & TGA_TOPTOBOTTOM) {
         dst = p->data[0];
         stride = p->linesize[0];
     } else { //image is upside-down
         dst = p->data[0] + p->linesize[0] * (h - 1);
         stride = -p->linesize[0];
     }

     interleave = flags & TGA_INTERLEAVE2 ? 2 :
                  flags & TGA_INTERLEAVE4 ? 4 : 1;

     if (colors) {
         int pal_size, pal_sample_size;

         switch (csize) {
         case 32: pal_sample_size = 4; break;
         case 24: pal_sample_size = 3; break;
         case 16:
         case 15: pal_sample_size = 2; break;
         default:
             av_log(avctx, AV_LOG_ERROR, "Palette entry size %i bits is not supported\n", csize);
             return AVERROR_INVALIDDATA;
         }
         pal_size = colors * pal_sample_size;
         if (avctx->pix_fmt != AV_PIX_FMT_PAL8) //should not occur but skip palette anyway
             bytestream2_skip(&s->gb, pal_size);
         else {
             int t;
             uint32_t *pal = ((uint32_t *)p->data[1]) + first_clr;

             if (bytestream2_get_bytes_left(&s->gb) < pal_size) {
                 av_log(avctx, AV_LOG_ERROR,
                        "Not enough data to read palette\n");
                 return AVERROR_INVALIDDATA;
             }
             switch (pal_sample_size) {
             case 4:
                 for (t = 0; t < colors; t++)
                     *pal++ = bytestream2_get_le32u(&s->gb);
                 break;
             case 3:
                 /* RGB24 */
                 for (t = 0; t < colors; t++)
                     *pal++ = (0xffU<<24) | bytestream2_get_le24u(&s->gb);
                 break;
             case 2:
                 /* RGB555 */
                 for (t = 0; t < colors; t++) {
                     uint32_t v = bytestream2_get_le16u(&s->gb);
                     v = ((v & 0x7C00) <<  9) |
                         ((v & 0x03E0) <<  6) |
                         ((v & 0x001F) <<  3);
                     /* left bit replication */
                     v |= (v & 0xE0E0E0U) >> 5;
                     *pal++ = (0xffU<<24) | v;
                 }
                 break;
             }
             p->palette_has_changed = 1;
         }
     }

     if ((compr & (~TGA_RLE)) == TGA_NODATA) {
         memset(p->data[0], 0, p->linesize[0] * h);
     } else {
         if (compr & TGA_RLE) {
             int res = targa_decode_rle(avctx, s, dst, w, h, stride, bpp, interleave);
             if (res < 0)
                 return res;
         } else {
             size_t img_size = w * ((bpp + 1) >> 3);
             uint8_t *line;
             if (bytestream2_get_bytes_left(&s->gb) < img_size * h) {
                 av_log(avctx, AV_LOG_ERROR,
                        "Not enough data available for image\n");
                 return AVERROR_INVALIDDATA;
             }

             line = dst;
             y = 0;
             do {
                 bytestream2_get_buffer(&s->gb, line, img_size);
                 line = advance_line(dst, line, stride, &y, h, interleave);
             } while (line);
         }

         if (flags & TGA_RIGHTTOLEFT) { // right-to-left, needs horizontal flip
             int x;
             for (y = 0; y < h; y++) {
                 void *line = &p->data[0][y * p->linesize[0]];
                 for (x = 0; x < w >> 1; x++) {
                     switch (bpp) {
                     case 32:
                         FFSWAP(uint32_t, ((uint32_t *)line)[x], ((uint32_t *)line)[w - x - 1]);
                         break;
                     case 24:
                         FFSWAP(uint8_t, ((uint8_t *)line)[3 * x    ], ((uint8_t *)line)[3 * w - 3 * x - 3]);
                         FFSWAP(uint8_t, ((uint8_t *)line)[3 * x + 1], ((uint8_t *)line)[3 * w - 3 * x - 2]);
                         FFSWAP(uint8_t, ((uint8_t *)line)[3 * x + 2], ((uint8_t *)line)[3 * w - 3 * x - 1]);
                         break;
                     case 16:
                         FFSWAP(uint16_t, ((uint16_t *)line)[x], ((uint16_t *)line)[w - x - 1]);
                         break;
                     case 8:
                         FFSWAP(uint8_t, ((uint8_t *)line)[x], ((uint8_t *)line)[w - x - 1]);
                     }
                 }
             }
         }
     }


     *got_frame = 1;

     return avpkt->size;
 }

 AVCodec ff_targa_decoder = {
     .name           = "targa",
     .long_name      = NULL_IF_CONFIG_SMALL("Truevision Targa image"),
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_TARGA,
     .priv_data_size = sizeof(TargaContext),
     .decode         = decode_frame,
     .capabilities   = AV_CODEC_CAP_DR1,
 };
	/*
	* Targa (.tga) image decoder
	* Copyright (c) 2006 Konstantin Shishkov
	*
	* This file is part of FFmpeg.
	*
	* FFmpeg 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.
	*
	* FFmpeg 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 FFmpeg; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	*/

	#include "libavutil/intreadwrite.h"
	#include "libavutil/imgutils.h"
	#include "avcodec.h"
	#include "bytestream.h"
	#include "internal.h"
	#include "targa.h"

	typedef struct TargaContext {
	GetByteContext gb;
	} TargaContext;

	static uint8_t advance_line(uint8_t start, uint8_t *line,
	int stride, int *y, int h, int interleave)
	{
	*y += interleave;

	if (*y < h) {
	return line + interleave * stride;
	} else {
	y = (y + 1) & (interleave - 1);
	if (y && y < h) {
	return start + y stride;
	} else {
	return NULL;
	}
	}
	}

	static int targa_decode_rle(AVCodecContext avctx, TargaContext s,
	uint8_t *start, int w, int h, int stride,
	int bpp, int interleave)
	{
	int x, y;
	int depth = (bpp + 1) >> 3;
	int type, count;
	uint8_t *line = start;
	uint8_t *dst = line;

	x = y = count = 0;
	while (dst) {
	if (bytestream2_get_bytes_left(&s->gb) <= 0) {
	av_log(avctx, AV_LOG_ERROR,
	"Ran ouf of data before end-of-image\n");
	return AVERROR_INVALIDDATA;
	}
	type = bytestream2_get_byteu(&s->gb);
	count = (type & 0x7F) + 1;
	type &= 0x80;
	if (!type) {
	do {
	int n = FFMIN(count, w - x);
	bytestream2_get_buffer(&s->gb, dst, n * depth);
	count -= n;
	dst += n * depth;
	x += n;
	if (x == w) {
	x = 0;
	dst = line = advance_line(start, line, stride, &y, h, interleave);
	}
	} while (dst && count > 0);
	} else {
	uint8_t tmp[4];
	bytestream2_get_buffer(&s->gb, tmp, depth);
	do {
	int n = FFMIN(count, w - x);
	count -= n;
	x += n;
	do {
	memcpy(dst, tmp, depth);
	dst += depth;
	} while (--n);
	if (x == w) {
	x = 0;
	dst = line = advance_line(start, line, stride, &y, h, interleave);
	}
	} while (dst && count > 0);
	}
	}

	if (count) {
	av_log(avctx, AV_LOG_ERROR, "Packet went out of bounds\n");
	return AVERROR_INVALIDDATA;
	}

	return 0;
	}

	static int decode_frame(AVCodecContext *avctx,
	void data, int got_frame,
	AVPacket *avpkt)
	{
	TargaContext * const s = avctx->priv_data;
	AVFrame * const p = data;
	uint8_t *dst;
	int stride;
	int idlen, pal, compr, y, w, h, bpp, flags, ret;
	int first_clr, colors, csize;
	int interleave;

	bytestream2_init(&s->gb, avpkt->data, avpkt->size);

	/* parse image header */
	idlen = bytestream2_get_byte(&s->gb);
	pal = bytestream2_get_byte(&s->gb);
	compr = bytestream2_get_byte(&s->gb);
	first_clr = bytestream2_get_le16(&s->gb);
	colors = bytestream2_get_le16(&s->gb);
	csize = bytestream2_get_byte(&s->gb);
	bytestream2_skip(&s->gb, 4); /* 2: x, 2: y */
	w = bytestream2_get_le16(&s->gb);
	h = bytestream2_get_le16(&s->gb);
	bpp = bytestream2_get_byte(&s->gb);

	if (bytestream2_get_bytes_left(&s->gb) <= idlen) {
	av_log(avctx, AV_LOG_ERROR,
	"Not enough data to read header\n");
	return AVERROR_INVALIDDATA;
	}

	flags = bytestream2_get_byte(&s->gb);

	if (!pal && (first_clr \|\| colors \|\| csize)) {
	av_log(avctx, AV_LOG_WARNING, "File without colormap has colormap information set.\n");
	// specification says we should ignore those value in this case
	first_clr = colors = csize = 0;
	}

	// skip identifier if any
	bytestream2_skip(&s->gb, idlen);

	switch (bpp) {
	case 8:
	avctx->pix_fmt = ((compr & (~TGA_RLE)) == TGA_BW) ? AV_PIX_FMT_GRAY8 : AV_PIX_FMT_PAL8;
	break;
	case 15:
	case 16:
	avctx->pix_fmt = AV_PIX_FMT_RGB555LE;
	break;
	case 24:
	avctx->pix_fmt = AV_PIX_FMT_BGR24;
	break;
	case 32:
	avctx->pix_fmt = AV_PIX_FMT_BGRA;
	break;
	default:
	av_log(avctx, AV_LOG_ERROR, "Bit depth %i is not supported\n", bpp);
	return AVERROR_INVALIDDATA;
	}

	if (colors && (colors + first_clr) > 256) {
	av_log(avctx, AV_LOG_ERROR, "Incorrect palette: %i colors with offset %i\n", colors, first_clr);
	return AVERROR_INVALIDDATA;
	}

	if ((ret = ff_set_dimensions(avctx, w, h)) < 0)
	return ret;

	if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
	return ret;
	p->pict_type = AV_PICTURE_TYPE_I;

	if (flags & TGA_TOPTOBOTTOM) {
	dst = p->data[0];
	stride = p->linesize[0];
	} else { //image is upside-down
	dst = p->data[0] + p->linesize[0] * (h - 1);
	stride = -p->linesize[0];
	}

	interleave = flags & TGA_INTERLEAVE2 ? 2 :
	flags & TGA_INTERLEAVE4 ? 4 : 1;

	if (colors) {
	int pal_size, pal_sample_size;

	switch (csize) {
	case 32: pal_sample_size = 4; break;
	case 24: pal_sample_size = 3; break;
	case 16:
	case 15: pal_sample_size = 2; break;
	default:
	av_log(avctx, AV_LOG_ERROR, "Palette entry size %i bits is not supported\n", csize);
	return AVERROR_INVALIDDATA;
	}
	pal_size = colors * pal_sample_size;
	if (avctx->pix_fmt != AV_PIX_FMT_PAL8) //should not occur but skip palette anyway
	bytestream2_skip(&s->gb, pal_size);
	else {
	int t;
	uint32_t pal = ((uint32_t )p->data[1]) + first_clr;

	if (bytestream2_get_bytes_left(&s->gb) < pal_size) {
	av_log(avctx, AV_LOG_ERROR,
	"Not enough data to read palette\n");
	return AVERROR_INVALIDDATA;
	}
	switch (pal_sample_size) {
	case 4:
	for (t = 0; t < colors; t++)
	*pal++ = bytestream2_get_le32u(&s->gb);
	break;
	case 3:
	/* RGB24 */
	for (t = 0; t < colors; t++)
	*pal++ = (0xffU<<24) \| bytestream2_get_le24u(&s->gb);
	break;
	case 2:
	/* RGB555 */
	for (t = 0; t < colors; t++) {
	uint32_t v = bytestream2_get_le16u(&s->gb);
	v = ((v & 0x7C00) << 9) \|
	((v & 0x03E0) << 6) \|
	((v & 0x001F) << 3);
	/* left bit replication */
	v \|= (v & 0xE0E0E0U) >> 5;
	*pal++ = (0xffU<<24) \| v;
	}
	break;
	}
	p->palette_has_changed = 1;
	}
	}

	if ((compr & (~TGA_RLE)) == TGA_NODATA) {
	memset(p->data[0], 0, p->linesize[0] * h);
	} else {
	if (compr & TGA_RLE) {
	int res = targa_decode_rle(avctx, s, dst, w, h, stride, bpp, interleave);
	if (res < 0)
	return res;
	} else {
	size_t img_size = w * ((bpp + 1) >> 3);
	uint8_t *line;
	if (bytestream2_get_bytes_left(&s->gb) < img_size * h) {
	av_log(avctx, AV_LOG_ERROR,
	"Not enough data available for image\n");
	return AVERROR_INVALIDDATA;
	}

	line = dst;
	y = 0;
	do {
	bytestream2_get_buffer(&s->gb, line, img_size);
	line = advance_line(dst, line, stride, &y, h, interleave);
	} while (line);
	}

	if (flags & TGA_RIGHTTOLEFT) { // right-to-left, needs horizontal flip
	int x;
	for (y = 0; y < h; y++) {
	void line = &p->data[0][y p->linesize[0]];
	for (x = 0; x < w >> 1; x++) {
	switch (bpp) {
	case 32:
	FFSWAP(uint32_t, ((uint32_t )line)[x], ((uint32_t )line)[w - x - 1]);
	break;
	case 24:
	FFSWAP(uint8_t, ((uint8_t )line)[3 x ], ((uint8_t )line)[3 w - 3 * x - 3]);
	FFSWAP(uint8_t, ((uint8_t )line)[3 x + 1], ((uint8_t )line)[3 w - 3 * x - 2]);
	FFSWAP(uint8_t, ((uint8_t )line)[3 x + 2], ((uint8_t )line)[3 w - 3 * x - 1]);
	break;
	case 16:
	FFSWAP(uint16_t, ((uint16_t )line)[x], ((uint16_t )line)[w - x - 1]);
	break;
	case 8:
	FFSWAP(uint8_t, ((uint8_t )line)[x], ((uint8_t )line)[w - x - 1]);
	}
	}
	}
	}
	}


	*got_frame = 1;

	return avpkt->size;
	}

	AVCodec ff_targa_decoder = {
	.name = "targa",
	.long_name = NULL_IF_CONFIG_SMALL("Truevision Targa image"),
	.type = AVMEDIA_TYPE_VIDEO,
	.id = AV_CODEC_ID_TARGA,
	.priv_data_size = sizeof(TargaContext),
	.decode = decode_frame,
	.capabilities = AV_CODEC_CAP_DR1,
	};