コード例 #1
0
static int cbs_read_se_golomb(CodedBitstreamContext *ctx, BitstreamContext *bc,
                              const char *name, int32_t *write_to,
                              int32_t range_min, int32_t range_max)
{
    int32_t value;
    int position, i, j;
    unsigned int k;
    uint32_t v;
    char bits[65];

    position = bitstream_tell(bc);

    for (i = 0; i < 32; i++) {
        if (bitstream_bits_left(bc) < i + 1) {
            av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid se-golomb code at "
                   "%s: bitstream ended.\n", name);
            return AVERROR_INVALIDDATA;
        }
        k = bitstream_read_bit(bc);
        bits[i] = k ? '1' : '0';
        if (k)
            break;
    }
    if (i >= 32) {
        av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid se-golomb code at "
               "%s: more than 31 zeroes.\n", name);
        return AVERROR_INVALIDDATA;
    }
    v = 1;
    for (j = 0; j < i; j++) {
        k = bitstream_read_bit(bc);
        bits[i + j + 1] = k ? '1' : '0';
        v = v << 1 | k;
    }
    bits[i + j + 1] = 0;
    if (v & 1)
        value = -(int32_t)(v / 2);
    else
        value = v / 2;

    if (ctx->trace_enable)
        ff_cbs_trace_syntax_element(ctx, position, name, bits, value);

    if (value < range_min || value > range_max) {
        av_log(ctx->log_ctx, AV_LOG_ERROR, "%s out of range: "
               "%"PRId32", but must be in [%"PRId32",%"PRId32"].\n",
               name, value, range_min, range_max);
        return AVERROR_INVALIDDATA;
    }

    *write_to = value;
    return 0;
}
コード例 #2
0
ファイル: binkaudio.c プロジェクト: elnormous/libav
static float get_float(BitstreamContext *bc)
{
    int power = bitstream_read(bc, 5);
    float f = ldexpf(bitstream_read(bc, 23), power - 23);
    if (bitstream_read_bit(bc))
        f = -f;
    return f;
}
コード例 #3
0
ファイル: faxcompr.c プロジェクト: elnormous/libav
int ff_ccitt_unpack(AVCodecContext *avctx, const uint8_t *src, int srcsize,
                    uint8_t *dst, int height, int stride,
                    enum TiffCompr compr, int opts)
{
    int j;
    BitstreamContext bc;
    int *runs, *ref = NULL, *runend;
    int ret;
    int runsize = avctx->width + 2;

    runs = av_malloc(runsize * sizeof(runs[0]));
    ref  = av_malloc(runsize * sizeof(ref[0]));
    if (!runs || !ref) {
        ret = AVERROR(ENOMEM);
        goto fail;
    }
    ref[0] = avctx->width;
    ref[1] = 0;
    ref[2] = 0;
    bitstream_init(&bc, src, srcsize * 8);
    for (j = 0; j < height; j++) {
        runend = runs + runsize;
        if (compr == TIFF_G4) {
            ret = decode_group3_2d_line(avctx, &bc, avctx->width, runs, runend,
                                        ref);
            if (ret < 0)
                goto fail;
        } else {
            int g3d1 = (compr == TIFF_G3) && !(opts & 1);
            if (compr != TIFF_CCITT_RLE &&
                find_group3_syncmarker(&bc, srcsize * 8) < 0)
                break;
            if (compr == TIFF_CCITT_RLE || g3d1 || bitstream_read_bit(&bc))
                ret = decode_group3_1d_line(avctx, &bc, avctx->width, runs,
                                            runend);
            else
                ret = decode_group3_2d_line(avctx, &bc, avctx->width, runs,
                                            runend, ref);
            if (compr == TIFF_CCITT_RLE)
                bitstream_align(&bc);
        }
        if (avctx->err_recognition & AV_EF_EXPLODE && ret < 0)
            goto fail;

        if (ret < 0) {
            put_line(dst, stride, avctx->width, ref);
        } else {
            put_line(dst, stride, avctx->width, runs);
            FFSWAP(int *, runs, ref);
        }
        dst += stride;
    }
    ret = 0;
fail:
    av_free(runs);
    av_free(ref);
    return ret;
}
コード例 #4
0
ファイル: faxcompr.c プロジェクト: elnormous/libav
static int find_group3_syncmarker(BitstreamContext *bc, int srcsize)
{
    unsigned int state = -1;
    srcsize -= bitstream_tell(bc);
    while (srcsize-- > 0) {
        state += state + bitstream_read_bit(bc);
        if ((state & 0xFFF) == 1)
            return 0;
    }
    return -1;
}
コード例 #5
0
ファイル: escape130.c プロジェクト: elnormous/libav
static int decode_skip_count(BitstreamContext *bc)
{
    int value;

    value = bitstream_read_bit(bc);
    if (value)
        return 0;

    value = bitstream_read(bc, 3);
    if (value)
        return value;

    value = bitstream_read(bc, 8);
    if (value)
        return value + 7;

    value = bitstream_read(bc, 15);
    if (value)
        return value + 262;

    return -1;
}
コード例 #6
0
ファイル: binkaudio.c プロジェクト: elnormous/libav
/**
 * Decode Bink Audio block
 * @param[out] out Output buffer (must contain s->block_size elements)
 * @return 0 on success, negative error code on failure
 */
static int decode_block(BinkAudioContext *s, float **out, int use_dct)
{
    int ch, i, j, k;
    float q, quant[25];
    int width, coeff;
    BitstreamContext *bc = &s->bc;

    if (use_dct)
        bitstream_skip(bc, 2);

    for (ch = 0; ch < s->channels; ch++) {
        FFTSample *coeffs = out[ch];

        if (s->version_b) {
            if (bitstream_bits_left(bc) < 64)
                return AVERROR_INVALIDDATA;
            coeffs[0] = av_int2float(bitstream_read(bc, 32)) * s->root;
            coeffs[1] = av_int2float(bitstream_read(bc, 32)) * s->root;
        } else {
            if (bitstream_bits_left(bc) < 58)
                return AVERROR_INVALIDDATA;
            coeffs[0] = get_float(bc) * s->root;
            coeffs[1] = get_float(bc) * s->root;
        }

        if (bitstream_bits_left(bc) < s->num_bands * 8)
            return AVERROR_INVALIDDATA;
        for (i = 0; i < s->num_bands; i++) {
            int value = bitstream_read(bc, 8);
            quant[i]  = quant_table[FFMIN(value, 95)];
        }

        k = 0;
        q = quant[0];

        // parse coefficients
        i = 2;
        while (i < s->frame_len) {
            if (s->version_b) {
                j = i + 16;
            } else {
                int v = bitstream_read_bit(bc);
                if (v) {
                    v = bitstream_read(bc, 4);
                    j = i + rle_length_tab[v] * 8;
                } else {
                    j = i + 8;
                }
            }

            j = FFMIN(j, s->frame_len);

            width = bitstream_read(bc, 4);
            if (width == 0) {
                memset(coeffs + i, 0, (j - i) * sizeof(*coeffs));
                i = j;
                while (s->bands[k] < i)
                    q = quant[k++];
            } else {
                while (i < j) {
                    if (s->bands[k] == i)
                        q = quant[k++];
                    coeff = bitstream_read(bc, width);
                    if (coeff) {
                        int v;
                        v = bitstream_read_bit(bc);
                        if (v)
                            coeffs[i] = -q * coeff;
                        else
                            coeffs[i] =  q * coeff;
                    } else {
                        coeffs[i] = 0.0f;
                    }
                    i++;
                }
            }
        }

        if (CONFIG_BINKAUDIO_DCT_DECODER && use_dct) {
            coeffs[0] /= 0.5;
            s->trans.dct.dct_calc(&s->trans.dct,  coeffs);
        }
        else if (CONFIG_BINKAUDIO_RDFT_DECODER)
            s->trans.rdft.rdft_calc(&s->trans.rdft, coeffs);
    }

    for (ch = 0; ch < s->channels; ch++) {
        int j;
        int count = s->overlap_len * s->channels;
        if (!s->first) {
            j = ch;
            for (i = 0; i < s->overlap_len; i++, j += s->channels)
                out[ch][i] = (s->previous[ch][i] * (count - j) +
                              out[ch][i] *          j) / count;
        }
        memcpy(s->previous[ch], &out[ch][s->frame_len - s->overlap_len],
               s->overlap_len * sizeof(*s->previous[ch]));
    }

    s->first = 0;

    return 0;
}
コード例 #7
0
ファイル: escape130.c プロジェクト: elnormous/libav
static int escape130_decode_frame(AVCodecContext *avctx, void *data,
                                  int *got_frame, AVPacket *avpkt)
{
    const uint8_t *buf  = avpkt->data;
    int buf_size        = avpkt->size;
    Escape130Context *s = avctx->priv_data;
    AVFrame *pic        = data;
    BitstreamContext bc;
    int ret;

    uint8_t *old_y, *old_cb, *old_cr,
            *new_y, *new_cb, *new_cr;
    uint8_t *dstY, *dstU, *dstV;
    unsigned old_y_stride, old_cb_stride, old_cr_stride,
             new_y_stride, new_cb_stride, new_cr_stride;
    unsigned total_blocks = avctx->width * avctx->height / 4,
             block_index, block_x = 0;
    unsigned y[4] = { 0 }, cb = 0x10, cr = 0x10;
    int skip = -1, y_avg = 0, i, j;
    uint8_t *ya = s->old_y_avg;

    // first 16 bytes are header; no useful information in here
    if (buf_size <= 16) {
        av_log(avctx, AV_LOG_ERROR, "Insufficient frame data\n");
        return AVERROR_INVALIDDATA;
    }

    if ((ret = ff_get_buffer(avctx, pic, 0)) < 0)
        return ret;

    bitstream_init(&bc, buf + 16, (buf_size - 16) * 8);

    new_y  = s->new_y;
    new_cb = s->new_u;
    new_cr = s->new_v;
    new_y_stride  = s->linesize[0];
    new_cb_stride = s->linesize[1];
    new_cr_stride = s->linesize[2];
    old_y  = s->old_y;
    old_cb = s->old_u;
    old_cr = s->old_v;
    old_y_stride  = s->linesize[0];
    old_cb_stride = s->linesize[1];
    old_cr_stride = s->linesize[2];

    for (block_index = 0; block_index < total_blocks; block_index++) {
        // Note that this call will make us skip the rest of the blocks
        // if the frame ends prematurely.
        if (skip == -1)
            skip = decode_skip_count(&bc);
        if (skip == -1) {
            av_log(avctx, AV_LOG_ERROR, "Error decoding skip value\n");
            return AVERROR_INVALIDDATA;
        }

        if (skip) {
            y[0] = old_y[0];
            y[1] = old_y[1];
            y[2] = old_y[old_y_stride];
            y[3] = old_y[old_y_stride + 1];
            y_avg = ya[0];
            cb = old_cb[0];
            cr = old_cr[0];
        } else {
            if (bitstream_read_bit(&bc)) {
                unsigned sign_selector       = bitstream_read(&bc, 6);
                unsigned difference_selector = bitstream_read(&bc, 2);
                y_avg = 2 * bitstream_read(&bc, 5);
                for (i = 0; i < 4; i++) {
                    y[i] = av_clip(y_avg + offset_table[difference_selector] *
                                   sign_table[sign_selector][i], 0, 63);
                }
            } else if (bitstream_read_bit(&bc)) {
                if (bitstream_read_bit(&bc)) {
                    y_avg = bitstream_read(&bc, 6);
                } else {
                    unsigned adjust_index = bitstream_read(&bc, 3);
                    y_avg = (y_avg + luma_adjust[adjust_index]) & 63;
                }
                for (i = 0; i < 4; i++)
                    y[i] = y_avg;
            }

            if (bitstream_read_bit(&bc)) {
                if (bitstream_read_bit(&bc)) {
                    cb = bitstream_read(&bc, 5);
                    cr = bitstream_read(&bc, 5);
                } else {
                    unsigned adjust_index = bitstream_read(&bc, 3);
                    cb = (cb + chroma_adjust[0][adjust_index]) & 31;
                    cr = (cr + chroma_adjust[1][adjust_index]) & 31;
                }
            }
        }
        *ya++ = y_avg;

        new_y[0]                = y[0];
        new_y[1]                = y[1];
        new_y[new_y_stride]     = y[2];
        new_y[new_y_stride + 1] = y[3];
        *new_cb = cb;
        *new_cr = cr;

        old_y += 2;
        old_cb++;
        old_cr++;
        new_y += 2;
        new_cb++;
        new_cr++;
        block_x++;
        if (block_x * 2 == avctx->width) {
            block_x = 0;
            old_y  += old_y_stride * 2  - avctx->width;
            old_cb += old_cb_stride     - avctx->width / 2;
            old_cr += old_cr_stride     - avctx->width / 2;
            new_y  += new_y_stride * 2  - avctx->width;
            new_cb += new_cb_stride     - avctx->width / 2;
            new_cr += new_cr_stride     - avctx->width / 2;
        }

        skip--;
    }

    new_y  = s->new_y;
    new_cb = s->new_u;
    new_cr = s->new_v;
    dstY   = pic->data[0];
    dstU   = pic->data[1];
    dstV   = pic->data[2];
    for (j = 0; j < avctx->height; j++) {
        for (i = 0; i < avctx->width; i++)
            dstY[i] = new_y[i] << 2;
        dstY  += pic->linesize[0];
        new_y += new_y_stride;
    }
    for (j = 0; j < avctx->height / 2; j++) {
        for (i = 0; i < avctx->width / 2; i++) {
            dstU[i] = chroma_vals[new_cb[i]];
            dstV[i] = chroma_vals[new_cr[i]];
        }
        dstU   += pic->linesize[1];
        dstV   += pic->linesize[2];
        new_cb += new_cb_stride;
        new_cr += new_cr_stride;
    }

    ff_dlog(avctx, "Frame data: provided %d bytes, used %d bytes\n",
            buf_size, bitstream_tell(&bc) >> 3);

    FFSWAP(uint8_t*, s->old_y, s->new_y);
    FFSWAP(uint8_t*, s->old_u, s->new_u);
    FFSWAP(uint8_t*, s->old_v, s->new_v);

    *got_frame = 1;

    return buf_size;
}
コード例 #8
0
ファイル: atrac3plusdec.c プロジェクト: Rodeo314/tim-libav
static int atrac3p_decode_frame(AVCodecContext *avctx, void *data,
                                int *got_frame_ptr, AVPacket *avpkt)
{
    ATRAC3PContext *ctx = avctx->priv_data;
    AVFrame *frame      = data;
    int i, ret, ch_unit_id, ch_block = 0, out_ch_index = 0, channels_to_process;
    float **samples_p = (float **)frame->extended_data;

    frame->nb_samples = ATRAC3P_FRAME_SAMPLES;
    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
        return ret;
    }

    if ((ret = bitstream_init8(&ctx->bc, avpkt->data, avpkt->size)) < 0)
        return ret;

    if (bitstream_read_bit(&ctx->bc)) {
        av_log(avctx, AV_LOG_ERROR, "Invalid start bit!\n");
        return AVERROR_INVALIDDATA;
    }

    while (bitstream_bits_left(&ctx->bc) >= 2 &&
           (ch_unit_id = bitstream_read(&ctx->bc, 2)) != CH_UNIT_TERMINATOR) {
        if (ch_unit_id == CH_UNIT_EXTENSION) {
            avpriv_report_missing_feature(avctx, "Channel unit extension");
            return AVERROR_PATCHWELCOME;
        }
        if (ch_block >= ctx->num_channel_blocks ||
            ctx->channel_blocks[ch_block] != ch_unit_id) {
            av_log(avctx, AV_LOG_ERROR,
                   "Frame data doesn't match channel configuration!\n");
            return AVERROR_INVALIDDATA;
        }

        ctx->ch_units[ch_block].unit_type = ch_unit_id;
        channels_to_process               = ch_unit_id + 1;

        if ((ret = ff_atrac3p_decode_channel_unit(&ctx->bc,
                                                  &ctx->ch_units[ch_block],
                                                  channels_to_process,
                                                  avctx)) < 0)
            return ret;

        decode_residual_spectrum(&ctx->ch_units[ch_block], ctx->samples,
                                 channels_to_process, avctx);
        reconstruct_frame(ctx, &ctx->ch_units[ch_block],
                          channels_to_process, avctx);

        for (i = 0; i < channels_to_process; i++)
            memcpy(samples_p[out_ch_index + i], ctx->outp_buf[i],
                   ATRAC3P_FRAME_SAMPLES * sizeof(**samples_p));

        ch_block++;
        out_ch_index += channels_to_process;
    }

    *got_frame_ptr = 1;

    return avctx->block_align;
}