mirror of https://git.ffmpeg.org/ffmpeg.git
rtjpeg: Convert to the new bitstream reader
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c60cda7cb4
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@ -18,8 +18,10 @@
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* License along with Libav; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include "libavutil/common.h"
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#include "get_bits.h"
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#include "bitstream.h"
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#include "rtjpeg.h"
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#define PUT_COEFF(c) \
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@ -28,34 +30,36 @@
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/// aligns the bitstream to the given power of two
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#define ALIGN(a) \
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n = (-get_bits_count(gb)) & (a - 1); \
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if (n) {skip_bits(gb, n);}
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n = (-bitstream_tell(bc)) & (a - 1); \
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if (n) \
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bitstream_skip(bc, n);
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/**
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* @brief read one block from stream
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* @param gb contains stream data
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* @param bc contains stream data
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* @param block where data is written to
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* @param scan array containing the mapping stream address -> block position
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* @param quant quantization factors
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* @return 0 means the block is not coded, < 0 means an error occurred.
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*
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* Note: GetBitContext is used to make the code simpler, since all data is
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* Note: BitstreamContext is used to make the code simpler, since all data is
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* aligned this could be done faster in a different way, e.g. as it is done
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* in MPlayer libmpcodecs/native/rtjpegn.c.
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*/
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static inline int get_block(GetBitContext *gb, int16_t *block, const uint8_t *scan,
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const uint32_t *quant) {
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static inline int get_block(BitstreamContext *bc, int16_t *block,
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const uint8_t *scan, const uint32_t *quant)
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{
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int coeff, i, n;
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int8_t ac;
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uint8_t dc = get_bits(gb, 8);
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uint8_t dc = bitstream_read(bc, 8);
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// block not coded
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if (dc == 255)
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return 0;
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// number of non-zero coefficients
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coeff = get_bits(gb, 6);
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if (get_bits_left(gb) < (coeff << 1))
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coeff = bitstream_read(bc, 6);
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if (bitstream_bits_left(bc) < (coeff << 1))
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return AVERROR_INVALIDDATA;
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// normally we would only need to clear the (63 - coeff) last values,
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@ -64,7 +68,7 @@ static inline int get_block(GetBitContext *gb, int16_t *block, const uint8_t *sc
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// 2 bits per coefficient
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while (coeff) {
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ac = get_sbits(gb, 2);
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ac = bitstream_read_signed(bc, 2);
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if (ac == -2)
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break; // continue with more bits
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PUT_COEFF(ac);
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@ -72,10 +76,10 @@ static inline int get_block(GetBitContext *gb, int16_t *block, const uint8_t *sc
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// 4 bits per coefficient
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ALIGN(4);
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if (get_bits_left(gb) < (coeff << 2))
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if (bitstream_bits_left(bc) < (coeff << 2))
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return AVERROR_INVALIDDATA;
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while (coeff) {
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ac = get_sbits(gb, 4);
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ac = bitstream_read_signed(bc, 4);
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if (ac == -8)
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break; // continue with more bits
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PUT_COEFF(ac);
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@ -83,10 +87,10 @@ static inline int get_block(GetBitContext *gb, int16_t *block, const uint8_t *sc
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// 8 bits per coefficient
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ALIGN(8);
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if (get_bits_left(gb) < (coeff << 3))
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if (bitstream_bits_left(bc) < (coeff << 3))
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return AVERROR_INVALIDDATA;
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while (coeff) {
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ac = get_sbits(gb, 8);
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ac = bitstream_read_signed(bc, 8);
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PUT_COEFF(ac);
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}
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@ -105,19 +109,19 @@ static inline int get_block(GetBitContext *gb, int16_t *block, const uint8_t *sc
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*/
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int ff_rtjpeg_decode_frame_yuv420(RTJpegContext *c, AVFrame *f,
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const uint8_t *buf, int buf_size) {
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GetBitContext gb;
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BitstreamContext bc;
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int w = c->w / 16, h = c->h / 16;
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int x, y, ret;
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uint8_t *y1 = f->data[0], *y2 = f->data[0] + 8 * f->linesize[0];
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uint8_t *u = f->data[1], *v = f->data[2];
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if ((ret = init_get_bits8(&gb, buf, buf_size)) < 0)
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if ((ret = bitstream_init8(&bc, buf, buf_size)) < 0)
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return ret;
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for (y = 0; y < h; y++) {
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for (x = 0; x < w; x++) {
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#define BLOCK(quant, dst, stride) do { \
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int res = get_block(&gb, block, c->scan, quant); \
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int res = get_block(&bc, block, c->scan, quant); \
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if (res < 0) \
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return res; \
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if (res > 0) \
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@ -142,7 +146,7 @@ int ff_rtjpeg_decode_frame_yuv420(RTJpegContext *c, AVFrame *f,
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u += 8 * (f->linesize[1] - w);
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v += 8 * (f->linesize[2] - w);
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}
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return get_bits_count(&gb) / 8;
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return bitstream_tell(&bc) / 8;
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}
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/**
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